Hi I live in Philippines. We were married year 2010 in Las Vegas and relocated in Philippines 2014. My husband passed away May 2016. He had a son in his first marriage & told me he had the last will of his dad in California but that was written before marriage. Can I still claim his bank accounts as a legal spouse even my name is not in the will?

As a Spouse you should have rights to property. Since you and he resided in the Philippines that law may need to be looked at to determine rights.  If US property and Will, the Spouse has rights to property even if not in the Will, especially if the Will was made before the marriage.

Also if the bank accounts included your name or you were pay on death for them you receive them regardless.