Recently, many superflares on solar-type stars have been discovered as white- light flares (WLFs). The statistical study found a correlation between their energies (E) and durations ({tau}): {tau}{propto}E^0.39^, similar to those of solar hard/soft X-ray flares, {tau}{propto}E^0.2-0.33^. This indicates a universal mechanism of energy release on solar and stellar flares, i.e., magnetic reconnection. We here carried out statistical research on 50 solar WLFs observed with Solar Dynamics Observatory/HMI and examined the correlation between the energies and durations. As a result, the E-{tau} relation on solar WLFs ({tau}{propto}E^0.38^) is quite similar to that on stellar superflares ({tau}{propto}E^0.39^). However, the durations of stellar superflares are one order of magnitude shorter than those expected from solar WLFs. We present the following two interpretations for the discrepancy: (1) in solar flares, the cooling timescale of WLFs may be longer than the reconnection one, and the decay time of solar WLFs can be elongated by the cooling effect; (2) the distribution can be understood by applying a scaling law ({tau}{propto}E^1/3^B^-5/3^) derived from the magnetic reconnection theory. In the latter case, the observed superflares are expected to have 2-4 times stronger magnetic field strength than solar flares.