Depends on the child. While earlier education is very beneficial to long term learning development, if a child is not mentally ready then in the short term they could struggle mightily, risk being held back or risk hating education as they struggle for many grades while playing catch up to the rest of the kids.
Your child is only a couple weeks off though. I'd see about testing for kindergarten, and if your child passes and seems ready to handle the challenge then go for it, because they'll be ahead of the curve later on. If you they fail the test, or even barely pass, and their attitude has you concerned about their readiness, then wait another year, or put them through but make sure there is supplemental education such as tutoring once a week or you and mom putting in extra time each day to go over and help with everything, and buy different multimedia education-enhancing things like games, videos, and books, to help ease the transition and improve the progression.