Provided is a program parallelizing method and a program parallelizing apparatus that enable to efficiently generate a parallelized program with shorter parallel execution time.An instruction is scheduled by referring to inter-instruction dependency. A dependency between an instruction in a function fp/f0 and an instruction of a function fq of its descendant is analyzed, and parallelization is performed with the analysis result. First, an instruction of a deeper function fq is relatively scheduled to analyze whether each instruction has dependency with an instruction of another function fp. When there is inter-instruction dependency, scheduling of the instruction of the function fq is performed so as to maintain the dependency and realize the shortest execution time.