The structure of the title compound, [Pt(C6H5)(2)(C6H12N3P)(2)] or [Pt(Ph)(2)(PTA)(2)] (where Ph is phenyl and PTA is 1,3,5triaza-7-phosphaadamantane), is discussed. Selected geometric parameters are: Pt-P = 2.2888 (16) and 2.2944 (17) Angstrom, Pt-C = 2.052 (5) and 2.064 (6) Angstrom, C-Pt-C = 84.6 (2)degrees and P-Pt-P = 99.28 (6)degrees. The effective cone angle for the PTA ligands was calculated as 113degrees.