[Objective]To optimize the extraction conditions of insoluble dietary fiber from apple pulp.[Method]The insoluble dietary fiber was extracted from the apple pulp by alkaline,and the optimal extraction conditions were determined by orthogonal experiment.[Result]The influential order of each factor on the extraction of insoluble fiber decreased in the order of solid-liquid ratio>alkali concentration>temperature>extraction time,and the optimal extraction technology was A3B1C2D2,that is,1:11(g/ml)of solid-liquid ratio,0.25 mol/L alkaline concentration,50℃ of extraction temperature and 2.0 hextraction time,under these conditions,the yield of insoluble dietary fiber was 35.46%.[Conclusion]The apple pulp contains rich dietary fiber,and the insoluble dietary fiber extracted from the apple pulp has great development value.