Osho was born Chandra Mohan Jain (चन्द्र मोहन जैन) in Kuchwada, a small village in the Narsinghpur District of Madhya Pradesh state in India, as the eldest of eleven children of a cloth merchant. At the time, an astrologer predicted that he might die before he was seven years old according to the birth chart.[16] His parents, who were Taranpanthi Jains, sent him to live with his maternal grandparents until he was seven years old.

Osho said this was a major influence on his growth because his grandmother gave him the utmost freedom and respect, leaving him carefree; without an imposed education or restrictions.

At seven years old he went back to his parents. He explained that he received a similar kind of respect from his paternal grandfather who was staying with them. He was able to be very open with his grandfather. His grandfather used to tell him, "I know you are doing the right thing. Everyone may tell you that you are wrong. But nobody knows which situation you are in. Only you can decide in your situation. Do whatsoever you feel is right. I will support you. I love you and respect you as well." He resisted his parents' pressure to get married.

He was a rebellious, but gifted student, winning the title of All-India Debating Champion.

He started his public speaking at the annual Sarva Dharma Sammelan held at Jabalpur since 1939, organised by the Taranpanthi Jain community into which he was born. He participated there from 1951 to 1968. Eventually the Jain community stopped inviting him because of his radical ideas.

Osho said he became spiritually enlightened on 21 March 1953, when he was 21 years old. He said he dropped all effort and hope. After an intense seven-day process he went out at night to a garden, where he sat under a tree:

“ The moment I entered the garden everything became luminous, it was all over the place – the benediction, the blessedness. I could see the trees for the first time – their green, their life, their very sap running. The whole garden was asleep, the trees were asleep. But I could see the whole garden alive, even the small grass leaves were so beautiful.
I looked around. One tree was tremendously luminous – the maulshree tree. It attracted me, it pulled me towards itself. I had not chosen it, god himself has chosen it. I went to the tree, I sat under the tree. As I sat there things started settling. The whole universe became a benediction.
”

He finished his studies at D. N. Jain College and the University of Sagar, receiving a B.A. (1955) and an M.A. (1957, with distinction) in philosophy. He then taught philosophy, first at Raipur Sanskrit College, and then, until 1966, as a Professor at Jabalpur University. At the same time, he travelled throughout India, giving lectures critical of socialism and Gandhi, under the name Acharya Rajneesh (Acharya means "teacher"; Rajneesh was a nickname he had been given by his family). In 1962, he began to lead 3- to 10-day meditation camps, and the first meditation centres (Jivan Jagruti Kendras) started to emerge around his teaching, then known as the Life Awakening Movement (Jivan Jagruti Andolan). He resigned from his teaching post in 1966.

In 1968, he scandalised Hindu leaders by calling for freer acceptance of sex; at the Second World Hindu Conference in 1969, he enraged Hindus by criticising all organised religion and the very institution of priesthood.

In 1969 a group of Osho's friends established a foundation to support his work. They settled in an apartment in Mumbai where he gave daily discourses and received visitors. The number and frequency of visitors soon became too much for the place, overflowing the apartment and bothering the neighbours. A much larger apartment was found on the ground floor (so the visitors would not need to use the elevator, a matter of conflict with the former neighbours).

On September 26, 1970 he initiated his first disciple or sannyasin at an outdoor meditation camp, one of the large gatherings where he lectured and guided group meditations. His concept of neo-sannyas entailed wearing the traditional orange dress of ascetic Hindu holy men. However, his sannyasins were not expected to follow an ascetic lifestyle.

1971–1980
From 1971, he was known as Bhagwan Shree Rajneesh. Shree means Sir or Mister; the Sanskrit word Bhagwan means "blessed one". It is commonly used in India as a respectful form of address for spiritual teachers.

The new apartment also proved insufficient, and the climate of Mumbai was deemed very bad for his delicate health. So, in 1974, on the 21st anniversary of his enlightenment, he and his group moved from the Mumbai apartment to a newly purchased property in Koregaon Park, in the city of Pune, a four-hour trip from Mumbai. Pune had been the secondary residence of many wealthy families from Mumbai because of the cooler climate (Mumbai lies in a coastal wetland, hot and damp, Pune is inland and much higher, so it is drier and cooler).

The two adjoining houses and six acres of land became the nucleus of an Ashram, and those two buildings are still at the heart of the present-day Osho International Meditation Resort. This space allowed for the regular audio and video recording of his discourses and, later, printing for worldwide distribution, which enabled him to reach far larger audiences internationally.

During one of his discourses in 1980, an attempt on his life was made by a Hindu fundamentalist.

Osho taught at the Pune Ashram from 1974 to 1981.

1981–1990
On 1 May 1981, having discoursed daily for nearly 15 years, Osho entered a three-and-a-half-year period of self-imposed public silence, and satsangs (silent sitting, with some readings from his works and music) took the place of his discourses.

In mid-1981, Osho went to the United States in search of better medical care (he suffered from asthma, diabetes and severe back problems). After a brief spell in Montclair, New Jersey, his followers bought (for US$6 million) a 64,000 acre (260 km²) ranch in Wasco County, Oregon, previously known as "The Big Muddy", where they settled for the next four years and legally incorporated a city named Rajneeshpuram.

Osho stayed in Rajneeshpuram as the commune's guest, living in a modest home with an indoor swimming pool. Over the coming years, he acquired fame for the large number of Rolls-Royces his followers bought for his use.

Osho ended his period of silence in October 1984. In July 1985, he resumed his daily public discourses in the commune's purpose-built, two-acre meditation hall. According to statements he made to the press, he did so against the wishes of Ma Anand Sheela, his secretary and the commune’s top manager.

Increasing conflicts with neighbours and the state of Oregon, as well as serious and criminal misconduct by the commune's management (including conspiracy to murder public officials, wiretapping within the commune, the attempted murder of Osho's personal physician, and a bioterrorism attack on the citizens of The Dalles, Oregon, using salmonella), made the position of the Oregon commune untenable. When the commune's management team who were guilty of these crimes left the U.S. in September 1985, fleeing for Europe, Osho convened a press conference and called on the authorities to undertake an investigation. This eventually led to the conviction of Sheela and several of her lieutenants. Although Osho himself was not implicated in these crimes, his reputation suffered tremendously, especially in the West.

In late October 1985, Osho himself was arrested in North Carolina as he was allegedly fleeing the U.S. Accused of minor immigration violations, Osho, on advice of his lawyers, entered an "Alford plea" – through which a suspect does not admit guilt, but does concede there is enough evidence to convict him – and was given a suspended sentence on condition that he leave the country.

Osho then began a world tour, speaking in Nepal, Greece and Uruguay, among others. Being refused entry visas by more than twenty different countries, he returned to India in July 1986, and in January 1987, to his old Ashram in Pune, India. He resumed discoursing there.

In late December 1988, he said he no longer wished to be referred to as Bhagwan Shree Rajneesh, and shortly afterwards took the name Osho.

On January 19, 1990, four years after his arrest, Osho died, aged 58, with heart failure being the publicly reported cause. Prior to his death, Osho had expressed his belief that his rapid health decline was caused by some form of poison administered to him by the U.S. authorities during the twelve days he was held without bail in various U.S. prisons. In a public discourse on 6 November 1987, he said that a number of doctors that were consulted had variously suspected thallium, radioactive exposure, and other poisons to account for his failing health:

“ It does not matter which poison has been given to me, but it is certain that I have been poisoned by Ronald Reagan's American government. ”

His ashes were placed in his newly built bedroom in one of the main buildings (LaoTsu House) at his last place of residence, his Ashram in Pune, India. The epitaph reads, "OSHO. Never Born, Never Died. Only Visited this Planet Earth between Dec 11 1931 – Jan 19 1990."