A slot machine includes a display device for displaying a symbol matrix display region in which plural types of symbols are displayed; a memory for storing data concerning a number of predetermined symbols arranged in the symbol matrix display region; and a processor for controlling the display device and the memory, the processor being programmed to: (a) execute a basic game; (b) rearrange the plural types of symbols in the symbol matrix display region during the basic game; (c) cumulatively store in the memory, the data concerning the number of the predetermined symbols from among the plural types of symbols, the predetermined symbols being rearranged in the symbol matrix display region during the basic game; (d) determine a number of times in executing a free game by executing a sub game by a number of times equal to the number of the predetermined symbols rearranged in the symbol matrix display region by referring to the data concerning the number of the predetermined symbols stored in the memory; and (e) execute the free game based on the number of times determined in the itemized (d).