The luminescence of Ce and Ce , Mn + co-doped BaB8O13 and SrB4O7 prepared in air is studied. The results show that tetravalent cerium ion can be reduced to trivalent state in the hosts and gives rise to efficient luminescence. Energy transfer between Ce3+ and Mn2+ is possible. Mn2+ ions can be efficiently sensitized by Ce 3+ and exhibit green and red emissions which implied that Mn2 + occupied the crystallographic sites of cations and boron sites of the anoins, respectively. The intensity ratio of red to green emission in matrix increases with the increasing of manganese concentration.