Just before 8am on April 5 the victim boarded a Preston-bound service at Blackpool North station.
During her journey a woman started shouting “paedo” and “you have my kids”.
She also turned to another passenger and racially abused him.
She then stood up, approached the victim and shouted “look at me” before grabbing her hair, punching and kicking her.
As a result of the attack, the victim sustained a split lip, black eyes and bruising to the face and body.
Officers have released an image of a woman they believe can help with their investigation.
Text 61016 or call 0800 40 50 40 quoting reference 99 of 05/04/22 or Crimestoppers on 0800 555 111.