A fungicidal composition having a synergistic effect is provided. The composition including active ingredients A and B. The active ingredient A is benziothiazolinone, the active ingredient B is one selected from benthiavalicarb-isopropyl, zoxamide, prothioconazole, boscalid, fenamidone, fluopicolide, famoxadone, pyraclostrobin, picoxystrobin or fluazinam, and the weight ratio of the two ingredients is from 1:50 to 50:1. The test results show that the fungicidal composition according to the present invention has an obvious synergistic effect, such that the application rate is reduced and the cost is lowered; and is useful in controlling certain particular fungal diseases on grain crops, vegetables, and fruits with a broadened fungicidal spectrum, a retarded resistance development of the fungi, and an improved control effect.