Abstract: Because of the poor interaction between carbon nanotubes(CNTs) and Pt nanoparticles in CNTs-supported Pt catalyst, the electrical conductivity between them is poor and the Pt nanoparticles may fall off or agglomerate. In this paper, the adsorption of Pt atom at different sites of the CNTs cap was investigated using the first principles theory. It is found that the average adsorption energy between (5,5) CNTs-Pt and (9,0) CNTs-Pt at different sites can be increased respectively by 12.7% and 19.6% by doping B, and 22.4% and 18.4% by doping N. The charge transfer between CNTs and Pt can also be significantly elevated compared with Pt adsorption at the tube side. In addition, the stability of the CNTs-Pt system can be increased by up to 133.8% (B-doping) and 237.3% (N-doping). The research indicates that doping B or N at the CNTs end can both improve the efficiency of CNTs-supported Pt catalyst.