The reduction rate of cold rolling has important effect for drawability of IF steel. The assigning of reduction rate in cold rolling is key for drawability in two-time cold rolling when total reduction is steady. It is proved by the test that Plastic Strain Ratio r-value is higher in two-time cold rolling than in one-time cold rolling at the same total reduction. If total reduction is steady, r-value is higher when the second reduction of cold rolling is larger than the first;, if total reduction increase, the r-value increase too.