mysql takes so much resources

[Teddy A Jasin]

Hi there,
I have 2 different websites using a single mysql server.
Today the websites respons very slow and when I check the mysql
proces i got the following info:
PID     %CPU     %MEM    VSZ  RSS  TT  STAT STARTED       TIME COMMAND
24339  51.6          0.7         6876 3704  p2- R    10:56AM    2:00.79     mysqld

So I suspect that my websites is slow because of the mysql server takes so much
of the CPU resources (51.6%).

So how to solve this problem? 
I tried restarting mysql then it again reach up until 50-60% of CPU.


Thanks
Teddy