We have investigated the electronic transport properties of Sn-phthalocyanine (SnPc) by using nonequilibrium Green's functions in combination with the density functional theory. The results show that, the spin-up/spin-down PDOS peak at 0.74 eV of SnPc will firstly move toward to the Fermi level and then be away from the Feimi level as the Sn atom is pulled out. A transform from spin-down filter to spin-up filter can be observed in parallel configuration due to spin flipping introduced by structural reorganization. While in anti-parallel configuration, the band structures of the two electrodes will play the dominant role in the electron properties of SnPc. The spin filter type conversion can be realized by pulling the Sn atom out of the SnPc or flipping the magnetic field of one electrode.