Parmeshwar Narayan Haksar (4 September 1913 – 25 November 1998) was an Indian bureaucrat and diplomat, best known for his two-year stint as Prime Minister Indira Gandhi's principal secretary (1971–73).

He authored the 'Stray Thoughts Memorandum' at the Congress Working Committee meeting in Bangalore which ultimately led to the removal of her political rivals, such as Morarji Desai.

[7] Until he vacated the position of Principal Secretary to Indira Gandhi, Haksar exercised significant influence on the formulation of domestic and foreign policies in Raisina Hill.

[4] As Principal Secretary, Haksar fashioned Indira Gandhi's decision about the timing and level of support to be given to the Bangladeshi freedom struggle, issuing directives from her private office to the top military leadership in some cases.

[8] The Prime Minister and her Principal Secretary subsequently fell out because Haksar reportedly disagreed with Indira's younger son, Sanjay, who aspired to be his mother's successor.

It was Sanjay who authorised a police raid on the Haksar family's shop in New Delhi, Pandit Brothers, deliberately humiliating the civil servant.

Haksar was noted for his strategising on the nationalisation of banks, insurance firms and foreign-owned oil companies, the 1971 Indo-Soviet Treaty and India's support to the liberation of what would become Bangladesh.