Son of Suresh Chandra Ghosh and Sarajubala Devi, he passed the Matriculation examination with a first division scoring very high percentage in both Bengali and mathematics.

Later in his career he worked in Jugantar and The Statesman and finally in the year 1951 went to Delhi to join Hindusthan Standard, the English publication of Anandabazar Patrika.

[2] Renowned as a short story and novel writer[3] Santosh Kumar also tried his hand in other literary forms like drama, poetry and essays.

[3] Nana Ranger Din (1952), Momer Putul (1958) which was later named as Shudhar Shohor, Mukher Rekha (1959), Renu Tomar Mon (1959), Jol Dao (1967), Swayang Nayak (1969), Sesh Namaskar Sricharaneshu Maa Ke[4] (1971), are some of the other novels that Santosh Kumar wrote.

In 'Mukher Rekha', 'Jal Dao', and 'Swayang nayak' and 'Sesh Namaskar: Sricharaneshu Maa ke',[4][6] where Santosh Kumar has combined the autobiographical and confessional mode of narration to deal with the roots of different social evils.

A continuous seeker of new fictional methods, he wrote 'Renu Tomar Mon' in second person point of view (which is still unique in Bengali literature) and at the same time combined poetry, essay and story in his book Mile Omile.