The fetal heart potential signal extraction program implements on a computer: a selection function that selects, from among multiple biopotential signals, a prescribed biopotential signal wherein the maternal heart potential signal component is large； an independent component analysis function that performs independent component analysis on the multiple biopotential signals； a periodic signal-detecting function that detects, in the biopotential signal selected by the selection function and each output signal from the independent component analysis, signals having periodic peaks as peak timing signals； an output signal selection function that uses the peak timing signal of the biopotential signal selected by the selection function as the reference input, a peak timing signal from among the output signals of the independent component analysis as a comparative input, and selects an output signal that has a peak timing differing from the peak timing signal of the biopotential signal； and a function that outputs the selected output signal.
