Macro taking too long time to run

Hello friends,
My macro code is taking to much time while running..its taking approx 1 hr to compair twoo sheets corresponding cell values.we have approx 20000 recors in each sheet.Is there any way to reduce time.

ok....actually my code is running so i ll show u after a while...ya there are lots of tasks which i m doing in my code like find one value of sheet one in another and then match the corresponding cell values.and there are approx 20000*70 records to compair like this