A method, a device and an encoder for controlling filtering of intra-frame prediction reference pixel point are disclosed. The method includes: when various reference pixel points in a reference pixel group of an intra-frame block to be predicted are filtered, and the target reference pixel point to be filtered currently is not an edge reference pixel point in a reference pixel group (S202), acquiring a pixel difference value between the target reference pixel point and n adjacent reference pixel points thereof (S203); and selecting a filter with the filtering grade thereof corresponding to the pixel difference value to filter the target reference pixel point (S204). For various reference pixel points not located at an edge in a reference pixel group, according to the local difference characteristics of these reference pixel points, filters with corresponding filtering grades are flexibly configured, thus providing flexibility and adaptivity to the filtering, achieving better effect.