The invention belongs to the field of powder metallurgy, in particular to a preparation method of a high-carbon and high-alloy amorphous prealloy powder and aims at solving the problems that an amorphous prealloy powder prepared in the prior art is difficult at melting and atomizing stages, easily blocks atomizing nozzles, and easily produces pore defects on an original interface, although softening deformation can be generated during spraying. The high-carbon and high-alloy amorphous prealloy powder is prepared by the adopting the following process: firstly, weighing raw materials and mixingthe materials; secondly, adding hard alloy balls, a forming agent and a wet grinding medium and carrying out ball milling in a protective atmosphere; thirdly, filtering and drying, so as to obtain theprepared high-alloy amorphous prealloy powder which comprises one or more than 1 weight percent of carbon,20 or more than 20 weight percent of transition metal elements, and the balance of iron family elements. According to the preparation method disclosed by the invention, the amorphous prealloy powder is prepared by adopting mild wet milling and spraying granulation process, so that the difficult problems of melting and atomizing of a traditional melting and atomizing process in preparation of the high-carbon and high-alloy amorphous prealloy powder are solved.