Is 7 too old for kindergarten?

It's older than average because generally kids start kindergarten at 5 and then turn 6 during the year. So normally when you're 6 turning 7 then you should be in first grade. However, it does depend on his development, so he's not necessarily "too old". Perhaps he's developmentally delayed so his parents held him back a year? But otherwise, if he is developing normally for his age then I don't understand why they would have waited this long to send him. And he may end up being bored if the work is too easy for him, and may find his peers too immature.

No not all. Whether a child is ready for kindergarten is not based on their age, it's based on their maturity level and skills. Some are ready at age 4, while some aren't ready until 7. Personally, I know a lot of kids who won't graduate until they're 19, including myself, and their intelligence and performance isn't affected by their age. So don't worry about it.

little bit too old,my niece is 7 and is in 2nd grade.

Thats not excatly too old:)