Dalmiya was born into a Marwari family[2] of the Baniya (tradesman) caste, originally hailing from Chirawa, Jhunjhunu district in Rajasthan and based in Kolkata for many decades.

Dalmiya's daughter, Baishali (born 1969), shortly after her father's death, joined the Trinamool Congress in 2016, and was immediately given the ticket to contest the assembly election from the Bally constituency.

[7] Along with civil servant Inderjit Singh Bindra and cricket administrator N. K. P. Salve, Dalmiya proposed the hosting of 1987 World Cup in the Indian subcontinent.

The proposal was opposed by the English Test and County Cricket Board, which had hosted all three previous World Cups.

However, in 1984, with support votes from associate nations, the proposal passed through International Cricket Council (ICC) with a huge majority.

Dalmiya's role is said to have been important, as the then ICC President Clyde Walcott was not in favor of discussing South Africa's re-admission to cricket.

[11] In 1993, Dalmiya along with Bindra won a legal battle against broadcaster Doordarshan to sell the television rights of cricket matches in India.

[7][12] Dalmiya and the then BCCI President Madhavrao Scindia, secured the Indian subcontinent the hosting rights for the 1996 World Cup, turning the tables on the favorites England.

Later the same year, he was involved in a major row with the ICC over what was called the 'Denness Affair' in which the ICC match referee and former England captain Mike Denness found Sachin Tendulkar guilty of a technical breach of the rules (misreported in the Indian media as an allegation of ball-tampering) and gave him a fine and suspended sentence, while also banning Virender Sehwag for one match for claiming a catch off a bump ball.

[20] Contracts to Indian team players, and pensions to former cricketers and umpires were first awarded in 2003 when Dalmiya was the Board's president.

[14] In the 2005 BCCI board elections, Dalmiya's candidate Ranbir Singh Mahendra was ousted by Indian government minister Sharad Pawar as the head cricket official of India.

[22] In July 2010, the Calcutta High Court dismissed charges against Dalmiya, and allowed him to contest the presidency of the Cricket Association of Bengal, which he subsequently won.

[25] Dalmiya was often cited in the media as the man responsible for commercializing cricket and making BCCI the richest board in the world.

[26] He was also credited with breaking Australia and England's "monopoly" of ICC and establishing the presence of Indian subcontinent in international cricket.