Three series of cyclometalated organoplatinum(ii) complexes [Pt(p-MeC6H4)(bhq)(L)], in which bhq is benzo[h]quinolinate and L is PPh3 (1a), PPh2Me (1b), or PPhMe2 (1c); [Pt(p-XC6H4)(bhq)(PPh2Me)], in which X is H (2a), F (2b), Bu-t (2c), OMe (2d), or Me (2e = 1b); and [Pt(bhq)X(PPh2Me)], in which X is CF3CO2 (3a), Cl (3b), or I (3c) were synthesized and fully characterized using multinuclear (H-1 and P-31) NMR spectroscopy and elemental analysis. Typical complexes [Pt(p-MeC6H4)(bhq)(PPhMe2)], 1c, [Pt(p-MeC6H4)(bhq)(PPh2Me)], 2e, and [Pt(bhq)Cl(PPh2Me)], 3b, were further characterized by single crystal X-ray crystallography. The photophysical properties of all the complexes were studied and the influence of changing the ancillary ligands and substituents on their luminescence properties were investigated and the assignments were confirmed by TD-DFT calculations.