The invention relates to a structural safety quick early warning method for pre-jacking of a steel beam. The method comprises the following steps of: (1) before jacking work begins, extracting an influence matrix S by adopting finite element analysis, inputting the influence matrix S into a safety early warning system, and setting an early warning value; (2) when jacking is performed, acquiring displacement data W in the jacking of the steel beam in real time; (3) performing calculation by employing the safety early warning system according to [Sigma]=WS to obtain real-time stress; and (4) determining whether the early warning value is within a limit value or not according to the early warning value, if not, stopping the jacking and publishing early warning, or else, performing continuousjacking. Compared to the prior art, the structural safety quick early warning method for pre-jacking of the steel beam employ an influence matrix method to obviously improve calculation efficiency soas to avoid that traditional measurement value control cannot cover all the jacking error combinations, and the structural safety quick early warning method directly takes the structure safety as theevaluation indexes and has more general applicability.