Experimental and computational methods were employed to study the effects of gallium (Ga) doping on the structural and electronic properties of lead sulphide (PbS). Chemical bath deposition method was used to prepare Ga doped and undoped PbS at a deposition temperature of 80 °C and a pH of 11. The X-ray diffraction results confirmed that the prepared Ga doped and undoped PbS had face centered cubic crystal structures with preferential orientations along the (111) plane. The experimental results further revealed that Ga doping had a considerable effect on the structural parameters and optical band gap of PbS. The density functional theory calculated electronic structure further confirmed that Ga doping can cause Fermi level pinning in PbS by introducing a gap state between the conduction and valence bands. In addition, the band structure calculations revealed that PbS is a direct band gap semiconductor with its Fermi level lying exactly in between valance and conduction bands. All the experimental and computational results in the present work established that Ga doping had a significant effects on the structural and electronic properties of PbS.