Mehra lost his mother on September 8 and the last rites were conducted in Delhi.
She was 73, Mehra's spokesperson said in a statement. A prayer meet will take place today in Delhi.
Mehra is best known for his films like 'Rang De Basanti' and 'Delhi 6'. He is presently working on his much talked about project 'Bhaag Milkha Bhaag' featuring Farhan Akhtar.