The 92-year-old Bollywood legend was admitted to the Lilavati hospital in suburban Bandra on December 25 and continues to be there.
"He is still in the hospital. He is improving...he is much better now," his son Sunil told PTI.
When asked about the reason behind Pran's long stay, he did not share any information.
Earlier in November last year, soon after Diwali, the yesteryear actor was admitted after a health scare but was soon discharged on November 24.
Pran is one of the most popular villains of Hindi cinema and has acted in around 350 films including 'Badi Behen', 'Jis Desh Mein Ganga Behti Hai', 'Half Ticket', Purab Aur Paschim', 'Don' and Zanjeer' among others.
In 2001, he was honoured with the Padma Bhushan by the Government of India for his contribution towards Indian cinema.