Anna Reshma Rajan comes from Aluva in Kerala. She worked as a nurse in Rajagiri Hospital in Kochi before foraying into films. She was identified by producer Vijay Babu and director Lijo Jose Pellissery after seeing her face in a hoarding in Kerala. They made her audition for the role of Lichy in Angamaly Diaries. Including her, the film introduced 86 debutant actors. She was born as Anna Reshma Rajan. In the film she is credited as Reshma Rajan. After that, she preferred to be credited as Anna Rajan. Her second film was Lal Jose directorial Velipadinte Pusthakam (2017), opposite Mohanlal.