The structural, electrical and optical properties of four halogen elements F, Cl, Br, I doped phosphorene (X-phosphorene) were investigated by applying first principle calculations based on density functional theory. X-phosphorene have different bonding characters based on Mulliken population and differential charge analysis. The ionization energies of halogen atoms in X-phosphorene shown that F, Cl, Br are p-type dopants while I is n-type. In terms of the bandgap type, F-phosphorene and I-phosphorene are indirect, while Cl-phosphorene and Br-phosphorene are direct, besides, it is worth to note that Cl-phosphorene and I-phosphorene are promising spin-gapless semiconductors. All X-phosphorene show the anisotropic transport property after calculating its carrier effective masses based on obtained E-k relationship. The absorption abilities of X-phosphorene are increased in UV-A and UV-B regions, as well as in visible and infrared regions over against the intrinsic condition.