A downhole power generation device and a separate-zone waterflooding device, which relate to the field of oil and gas development technologies. The downhole power generation device comprises a housing extended axially and a rotating wheel, a striking mechanism and a piezoelectric bimorph provided in the housing. The piezoelectric bimorph is axially extended and circumferentially distributed around an axis of the housing, with one end of the piezoelectric bimorph being fixed. The rotating wheel is in transmission connection with the striking mechanism and can be rotated by fluid to drive the striking mechanism to rotate. The striking mechanism can touch the other end of the piezoelectric bimorph during rotation so that the piezoelectric bimorph vibrates back and forth.