We present what is to our knowledge the first experimental study of light-induced reflectivity changes at an alpha-Ga/Si interface irradiated by femtosecond and picosecond laser pulses. After exposure, the reflectivity can increase from R?0.55 , which is typical for alpha-Ga , to R?0.8 , which is close to that of liquid Ga. The initial step in the reflectivity change of 2-4 ps is resolved with 150-fs laser pulses. The light-induced reflectivity change relaxes during 100ns-10 mus , depending strongly on the background temperature of the Ga mirror and the laser fluence.