Through previous findings of green-light-emitting Ba2SiO4 phase in full-color Ba3MgSi2O8:Eu2+,Mn2+ phosphor for near-UV GaN-based white-light-emitting diodes, we present a route to compensate green band emission for full-color band emission by intentionally adding Al ion to promote the formation of green-light-emitting Ba2SiO4 and BaAl2O4 phases in Ba3MgSi2O8. The variation of Al-added amount leads to amount change of each phase in the mixed phases and adjustable energy transfer of Eu-Mn on sites in different hosts of phases are verified, consequently full-color band emission could be achieved in the potential application of white light.