SMBI (supersonic molecular beam injection), as an effective fueling method forfusion plasmas, has been widely used on the HL-2A tokamak and other fusion devices. Twodifferent types of SMBI system are now installed on HL-2A. One is an electromagnetic valveinjector on the low field side (LFS), and the other is a pneumatic valve injector on the high fieldside (HFS). A new electron density record n_e= 4.7×10~(19)m~(-3), which exceeds both the Greenwalddensity limit and the maximum density obtained by gas puffing (GP), was obtained on HL-2Awith single-null-divertor operation. The HFS injection system is still under test, however, itsoutstanding fueling characteristics have already been observed, e.g. it has higher fueling efficiencycompared to the LFS system. This excellent feature is still preserved during the process of ECRH. SMBI (supersonic molecular beam injection), as an effective fueling method forfusion plasmas, has been widely used on the HL-2A tokamak and other fusion devices. Twodifferent types of SMBI system are now installed on HL-2A. One is an electromagnetic valve object on A new electron density record n_e = 4.7 × 10 ~ (19) m ~ (-3), which exceeds both the Greenwalddensity (LFS), and the other is a pneumatic valve injector on the high fieldside limit and the maximum density obtained by gas puffing (GP), was obtained on HL-2A with single-null-divertor operation. However, its honorable fueling characteristics have been observed, eg it has higher fueling efficiencycompared to the LFS system. This excellent feature is still preserved during the process of ECRH.