The interaction between meso-tetraarylporphyrinato magnesium(ІІ) [MgT(4-X)PP] (X=H, CH 3 , and CH(CH 3 ) 2 ) and PCl 3 , as an electron acceptor, produced new molecular complexation [MgT(4-X)PP(PCl 3 ) 2 ]. The synthesized molecular complexes were characterized by ( 1 H, 31 P) NMR, UV–Vis, FT-IR spectroscopies and electric conductivity. In these molecular complexes, the central core of porphyrin, corrugates and two lone electron pairs of nitrogen atoms in the metalloporphyrin act as σ-electron donors to a phosphorous atom in PCl 3 and the second PCl 3 molecule acts as a ligand to magnesium(II) ion. The molar ratio of metalloporphyrin to PCl 3 in the molecular complexes was 1:2. The synthesized molecular complexes in acetone solvent showed no electric conductivity.