This review summarized and analyzed the structural parameters of 174 monomeric organoplatinum complexes with an inner coordination sphere of trans-PtP 2 C 2 . These complexes crystallized in four crystal systems: hexagonal (x2), orthorhombic (x13), triclinic (x76), and monoclinic (x84). These complexes, on the basis of the coordination mode of the respective donor ligands, can be divided into the seven sub-groups: Pt(PL) 2 (CL) 2 , Pt(PL) 2 (η 2 -C 2 L), Pt(η 2 -P 2 L)(CL) 2 , Pt(PL)(η 2 -P,CL)(CL), Pt(η 2 -P,CL) 2 , Pt(η 3 -P,C,PL)(CL), and Pt(η 3 -C,P,CL)(PL). The chelating ligands create 4-, 5-, 6-, 16-, 17-, 18-, and 19-membered rings. The total mean values of Pt-L bond distances are 2.055 Å (C) and 2.300 Å (P). There are examples that exist in two isomeric forms and are examples of distortion isomerism. The structural parameters of trans-PtP 2 C 2 are discussed with those of cis-PtP 2 C 2 derivatives.