In recent years, platinum-based alloys have been widely used in optics, electricity, magnetism and catalysis owing to their excellent deformation resistance, corrosion resistance and high hardness. Therefore, based on the CALYPSO crystal structure prediction technology, the most stable structure of Pt3Li, Cmmm-Pt3Li, was obtained. Subsequently, the Li atoms in Cmmm-Pt3Li were replaced with metal atoms M (where M = Na, Ti, Fe, Ni, Cu, Zn, Zr, Ag, and Cd), resulting in nine more stable Cmmm-Pt3M alloy structures. Then, phonon spectra, elastic constants, and formation energy calculation investigations were conducted to verify their structural stability. Electronic structure calculation results indicated that the metallicity contributions of these 10 alloys mainly originated from the Pt -d orbitals. Moreover, compared with the widely studied fcc-Pt3M structures, the Cmmm structures of Pt3Na, Pt3Cu, Pt3Zn, Pt3Ag, Pt3Cd were energetically favorable. (c) 2022 Elsevier B.V. All rights reserved.