i think it depends on his eating overall. if he eats a variety of food but just doesn't like food really sweet that may simply reflect his personal preferences. but if he eats very few foods it could indicate a sensory issue or that he is super taster (not serious -- just more sensitive to the tastes in food). if you feel his nutrition and growth is affected see his pediatrician for a referral to a feeding therapist who can help you figure out what is going on. good luck!
you asked: my son is 6 year old he don't like to eat those food which taste sweet is there any disorder in his taste bud