Abstract: The vacuum flat glass will improve the efficiency of box-type flat plate solar energy collectors group. The efficiency of the solar energy collectors group that respectively use the vacuum flat glass and ordinary hollow flat glass as its transparent cover was studied. Meanwhile, a lot of comparative experiments between them were conducted.The results showed that the efficiency of the box-type solar energy collectors that consisted of vacuum flat glass increased by 15% than that of the ordinary hollow flat glass. It demonstrates that vacuum flat glass can improve the efficiency of the box-type solar energy collector. So it has a good future in the application of box-type solar energy collectors group.