The invention relates to a hydrorefining catalyst and applications thereof, wherein the hydrorefining catalyst contains a carrier, at least a non-noble metal component selected from the group VIII and supported on the carrier, at least a metal component selected from the group VIB and supported on the carrier, and at least an alkali metal component selected from lithium, sodium, potassium and rubidium and supported on the carrier, and is characterized in that the content of the non-noble metal component selected from the group VIII is 0.5-8 wt% (calculated as the oxide), the content of the metal component selected from the group VIB is 4-30 wt% (calculated as the oxide), the alkali metal component content is 1-7 wt% (calculated as the oxide) by adopting the catalyst as the reference, and the carrier is alumina and prepared from hydrated alumina. Compared with the catalyst in the prior art, the catalyst of the present invention has the following advantages that the catalyst provides high hydrogenation activity and high selectivity for the diolefin in the gasoline distillate oil, and is particularly suitable for carrying out the hydrorefining using the hydrogenation-diolefin removing as the purpose on the gasoline distillate oil containing the diolefin.