jasnoor ji
Diwali or Deepwali is not a Sikh holiday. Many Sikhs do celebrate Diwali as a cultural tradition because of their roots in Inida, its culture and its history. However Diwali has no signficance to Sikhi.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=33305
More discussion at this link
http://www.sikhphilosophy.net/hard-t...d-sikhism.html
A few days before Diwali in 1619, Guru Hargobind led 52 Hindu princes out of the Gwalior fort where they were imprisoned with him. Bandi Chor Diwas literally means Prisoner Release Day. Thus the Sikh day of remembrance of Bandi Chor Diwas falls in Diwali each year and that is an important day for Sikhs.