The invention discloses a texture description method and system based on an improved local binary pattern. According to the invention, on one hand, the method includes extracting all equivalent modesin an original image; extracting all non-equivalent modes in the original image at the same time, taking a part of non-equivalent modes with high occurrence frequency from the non-equivalent modes asdominant non-equivalent modes based on the occurrence frequency of each type of non-equivalent modes, and constructing a mixed mode by utilizing all the equivalent modes and all the non-equivalent modes; on the other hand, the method includes selecting a rotary encoder or a natural encoder for hybrid encoding according to the image noise condition, and when the image is in a normal state, selecting the rotary encoder; and when the image is in a light alarm state, selecting a natural encoder. According to the method, texture description information in a non-equivalent mode is mined, the problemthat the texture description capability is reduced after a traditional LBP ignores the non-equivalent mode is solved, meanwhile, two coding modes which are freely switched according to the image noise degree are provided, and the anti-noise performance of the texture description process is improved.