Photoelectric encoder has static and dynamic characteristics. The analysis of photoelectric encoder′s errors is limited in static characteristics. In order to make the photoelectric encoder dynamic characteristics perfection, the dynamic errors of small absolute photoelectric encoder from bearing rocking, range-frequency respond, data handling delay and so on are researched. By analysising the relationship between angle speed and dynamic errors, the regular pattern of dynamic errors and angle speed are obtained. Analysis results show that the dynamic error of an encoder which h code carves are composed by 1, h and constant products. By the changing of speed, the range of these component products also change. Thereby the characteristics of the encoder are affected. The research results can be applied to the analysising and controlling of photoelectric encoder′s dynamic characteristics, as well as providing theory for the improvement of photoelectric encoder′s dynamic characteristics.