The invention discloses a method for preparing high-fluidity wide-distribution polypropylene and a product thereof. The method uses propylene for homopolymerization or copolymerization. A catalyst system consists of a component A, a component B and a component C, wherein the component A is a supported solid Ziegler-Natta catalyst taking magnesium, titanium, halogen and an internal electron donor as main components; the component B is an alkyl aluminum cocatalyst; and the component C is an external electron donor, and is a mixture of tetraethoxy silane and dicyclopentyl dimethoxy silane or diisobutyldimethoxysilane, wherein the dicyclopentyl dimethoxy silane or the diisobutyldimethoxysilane accounts for 0.1 to 10 percent of the total molar weight of the mixture; the component A, the component B and the component C are expressed by the content of Ti, the content of Al and the content of Si, and the molar ratio of Si to Ti is 1 to 100, and the molar ratio of Al to Si is 1 to 100 respectively; the polydispersity index of the product is between 6 and 20; and the melt index of the product with the mass of 2.16Kg at the temperature of 230 DEG C is between 20 and 200g/10min.