Chances are no. I had a gold fish with one of mine and it lived 6 years together. the gold fish died and I got another and then Japanese fish bit it tail but then didnt kill it. It just depends on the Fighting fish I would try introducing them between glass or plastic separation. if your fighting fish exhibits gill faring do not put your other fish in with it.
Its Siamese fighting fish..Bettas will eat anything they can fit in their mouths, so the fish has to have some size to it. How big is its tank, anyway? Could be there is no room for another fish.
they are known to be very violent fish, given their name
its better to be more specific to what kind of fish you are going to put with them. Only a small handful of fish can be with a beta.
Make sure the small fish doesn't challenge the beta, because the beta WILL win
My betta pretty much left the others alone. They get aggressive with members of their own species, but usually not with others. If you had baby guppies then yes, it would eat them, but adult guppies, no.