I recently changed my battery and alternator they are both brand new but my battery light keeps coming on could it be a fuse?

if you bought an aftermarket alternator>>say at the ZONE or a parts house,then you may just have a bad alternator right out of the box!! if that's the case,then you drained your new battery down to nothing,and you will see crazy things happen,and then it will strand you somewhere! take it to have the charging system tested. first, the battery must have a FULL CHARGE on it,for the parts house to test the alternator while it's still mounted on the car.OR,take em both off/out of the car and take both to the parts house with you.

Using a volt meter set to DC scale .. TEST the alternator output voltage at the battery terminals .. Should see approx 14 volts .. Yes it is very possible it is a failed fuse! .. The fuses can also be TESTED using the volt meter or a 12 volt test light.

It is true that many of the aftermarket rebuilt parts are not that reliable, but if you still have the exact same problem from the beginning and the new parts did nothing to fix it, then something is being missed. Intermittent short to ground in the light wire so the light comes on at times? Does your battery actually go dead? If yes you still may have a charging system problem. Have a qualified mechanic check your car. Pay for accurate tests,not guess work.