The invention belongs to the technical field of internet finance and block chain, and proposes a crowdfunding lottery method, the method comprising: after the success of crowdfunding support, sequentially numbering each lot of crowdfunding according to the sequence of crowdfunding; After a certain period of time, at least one parameter related to the blockchain; obtain the sequence of crowdfunding numbers after scrambling; according to the target number of crowdfunding, select the number of crowdfunding after scrambling as the lottery number in turn. The present invention also proposes a crowd-supported crowdfunding successful lottery system, which includes a crowdfunding numbering module, a module for selecting relevant block chain parameters, a reordering module, and a module for selecting a winning lottery numbering module. The crowdfunding lottery method and system of the present invention do not require third-party impartiality and supervision during the whole lottery process, and are just, open and fair, and the algorithm of the present invention is simple and convenient.