Cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethane diaryl ethene-doped polymer methyl methacrylate (PMMA) film samples were prepared(with weight percent of 10%).Based on the photoinduced change of the film absorption,the bistable all-optical switching based on diar ylethene doped films is composed.375nm (CW,40mW) and 532nm (CW,5mW) lasers were used as exciting li ght to irradiate the film samples,respectively,and 632.8nm (CW,3μW) laser was as th e probe light,we obtain the bistable all-optical switching by using the film samples in experim ent,and the modulation depth of the switching is 8.2% with rising time of 36s and down time of 47s. Based on the two level photochromic theory,the experimental results and the mechanism of the swi tching are analyzed deeply.The bistable all-optical switching has advantages of simplicity and bei ng easy to realize,so it has the potential application value in the development of low speed all-optical swi tching.