I am running mysql on my dedicated server, there isn't much load but mysql always take 29% cpu and sometimes it shows 80% cpu and memory is between 9% to 35%

I have checked my sql process list mysqladmin -i2 processlist but couldn't found any query that cause this problem.

I was wondering if its fine for mysql server to take all the time 29% cpu usage I never seen below that.

Any one can help me to troubleshoot this problem?