The purpose of the present invention is to provide a method for selecting an iPS cell clone with which tumor formation is less likely even when caused to differentiate, and a method for selecting a gene used in the method for selecting the same. As one embodiment, the expression level is examined with regards to at least one gene in any gene group from among first through tenth gene groups in an iPS cell clone in an undifferentiated state, whereby there is selected an iPS cell clone in which tumor formation is less likely even when caused to differentiate. Also, the expression level of a gene belonging to a candidate gene group including one or more genes is examined in each iPS clone in an undifferentiated state in relation to a plurality of first iPS cell clones that cannot differentiate normally or that are likely to form a tumor when differentiated and a plurality of second iPS cell clones that are less likely to form a tumor, whereby there is selected a gene used in the method for selecting an iPS cell c
