Yes, Jews can eat tuna. In fact, many Jews consider tuna to be a kosher fish. There are a few reasons for this. First, tuna is a type of fish that has scales and fins, which are both considered to be kosher signs. Second, tuna is not a predatory fish, so it is not considered to be an unclean animal. Finally, most brands of canned tuna are processed in factories that also process other kosher fish, so the tuna is considered to be Kosher by default.