Career with Indian National Congress

Mukherjee started his political career as a student activist during his higher education in Kolkata. He joined the Chhatra Parishad, a student organisation affiliated to the Indian National Congress, in the 1960s. During this period he made the acquaintance of Priya Ranjan Dasmunsi.^[3]

Mukherjee was considered one of the two close aides of former prime minister Indira Gandhi, along with Priya Ranjan Dasmunsi. CPIM leaders used a slogan "Indirar dui putra Priyo Ranjan o Subrata" (transl. Indira's two sons Priya Ranjan and Subrata).

In 1971 and 1972, Mukherjee was elected to the legislative assembly from the Ballygunge Assembly constituency. In 1972, he was appointed Minister of State in the Siddhartha Shankar Ray ministry as Minister of Information and Cultural Affairs. He also held an additional responsibility as Minister of State for local government.

He lost the Ballygunge Assembly constituency when the Congress party was defeated by the Left Front amid huge anti-incumbency voting patterns. In 1982, he shifted to the Jorabagan Assembly constituency and represented it till 1996. He was elected to the Legislative Assembly from Chowranghee in 1996 and 2001.

Career with All India Trinamool Congress

In 1999, he joined with Mamata Banerjee, parting ways with the Indian National Congress.^[4] This decision came from the Congress MLA, as INTUC denied him the nomination to the governing body of the ILO for the second term.^[5] He was made the Mayor of Kolkata in 2000, as a Trinamool Congress candidate. However, even after being the Mayor as a Trinamool leader, he decided not to resign as a Congress member of the Legislative Assembly.^[6] As Mayor, he had planned a 300 ft-high Kolkata gate on EM Bypass, which would have cost Rs. 20-crore.^[7] However, the project could not go ahead, as it could not obtain clearance from the Pollution Control Board.

Mukherjee was also elected to the Assembly on a Trinamool Congress ticket in 2001 from Chowrighee. He also contested the Lok Sabha elections in 2004 from Calcutta North West constituency, but lost.

Polls of Kolkata Municipal Corporation

Ahead of the civic polls in 2005, Mukherjee quit Trinamool Congress following differences with the party chief, and joined the Nationalist Congress Party. He was able to cobble up an alliance with Congress and several marginal players under the platform of Paschimbanga Unnayan Mancha. Although he was able to get elected to the corporation, his front suffered a humiliating defeat.

Even after leaving Trinamool Congress, he did not resign as a Trinamool member in the legislative assembly until the end of its term in 2006.

Later career

In the 2006 state elections, he came third in the Chowranghee seat as a Congress candidate. In 2006, the Congress had also fielded Mukherjee for the biennial election for a Rajya Sabha seat, but he failed to win.

In 2009, he fought from Bankura Lok Sabha constituency on the Congress ticket and lost.

In May 2010, Mukherjee left the Indian National Congress again and rejoined Trinamool Congress, leaving the post of Pradesh Congress Working President.^[8] He contested the 2011 Assembly elections from the Ballygunge seat.

Cabinet Minister

Pranab Mukherjee being received by the Governor of West Bengal, Shri M.K. Narayanan and West Bengal MIC, Public Health Engineering and Panchayat & Rural Development, Shri Subrata Mukherjee, on his arrival.

In 2011, after the Trinamool Congress won a majority in the West Bengal Legislative Assembly, he was made Minister for Public Health Engineering under Chief Minister Mamata Banerjee. In December 2011, he was given the additional charge of Panchayati Raj & Rural Development ministry, and replaced Chandranath Sinha.^[9]

In February 2012, he was made the All India President of the INTTUC, instead of Sobhandeb Chatterjee.^[10] In the 2019 Loksabha elections, he fought from Bankura and lost to Subhas Sarkar of the BJP. He won with huge margin in 2021 vidhan sabha election from Ballygunge.