Nano composites/alloys contain noble metal nanostructures exhibit a wide theoretical and experimental interest in the field of optic/plasmon or fuel cells. In this study, the Pd/Pt nanotriangular nanosheets with controlled shape and composition were synthesized by a simple approach at 60 o C for 120 min. The morphology, structure, and composition of prepared Pd/Pt nanotriangular nanosheets were determined by transmission electronic microscopy (TEM), and X-ray diffraction (XRD) techniques. Moreover, the plasmon property of this synthesized Pd/Pt nanotriangular nanosheets (Pd/Pt NTANSs) was also observed using the Raman (SERS) method. The results showed that Pd/Pt nanotriangular nanosheet (Pd/Pt NTANS) provided a SERS sensitivity of about ~1.6 times that of Pd NS substrate for the detection of Rd3B. This method could create a general approach for the shape-controlled synthesis of bimetallic Pt/M (M = Pd, Cu, Au, Mo, Mn, etc.) triangular nanocatalysts for promising applications in biosensors, plasmonics, and optics in the future.