A microporous membrane roll (33) comprises cores (1, 11, 21, 31) formed in whole or in part from electrically conductive members (12, 13), and microporous membranes (34, S) which are wound around the cores (1, 11, 21, 31). A first surface (100) and a second surface (200) of the microporous membranes (34, S) are respectively equivalently charged with antipolar charges (102, 201). A method of manufacturing the microporous membrane roll (33) includes diselectrifying the microporous membranes (34, S) with a diselectrifier (35), and winding the microporous membranes (34, S) around the cores (1, 11, 21, 31) formed in whole or in part from the electrically conductive members (12, 13). When the microporous membranes (34, S) are unwound from the cores (1, 11, 21, 31), the microporous membranes (34, S) are prevented from being drawn toward either the microporous membrane roll (33) or peripheral devices by static electricity. The microporous membranes (34, S) are useful as a separator in either a fuel cell or a secondary battery.