The invention relates to a picture processing method and a detecting method for micro block difference between different pictures. And the picture processing method comprises the steps of: first, providing a picture macro block, which is a macro block in a processed picture; applying the detecting method on at least two pictures before the processed picture in picture input sequence to obtain a macro block difference table, where if the processed picture is a P-picture, determining whether to encode the picture macro block according to the macro block difference table or not.