Embodiments of the invention provide a software memory security detection method and system. The method comprises the steps of determining multiple preset test case files of to-be-tested software through symbol execution, and converting the preset test case files into initial input seeds of guided variation-based fuzzy testing; and based on all the initial input seeds, performing the guided variation-based fuzzy testing on the to-be-tested software, wherein the guided variation is variation performed according to a coverage range of a program in the to-be-tested software. According to the software memory security detection method and system provided by the embodiments of the invention, the test case files generated by the symbol execution are fully utilized; meanwhile, the variation in thefuzzy testing is improved to obtain a guided variation method; and the symbol execution is combined with the guided variation, and the seeds meeting the condition in all the initial input seeds are subjected to the guided variation, so that the variation effectiveness is improved and the resources are saved.