TaSi2 nanoparticles have been synthesized on highly oriented pyrolytic graphite (HOPG) by ablating high purity TaSi2 target using pulsed laser ablation (PLA) technique. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) are applied to analyze the surface morphology and chemical states of the sample. The SEM results reveal that the average size and surface density of nanoparticles are 10nm and 1×1012cm-2 respectively;The XPS spectra show that the surface chemical elements of the nanoparticles on the HOPG substrate include Ta,Si,C and O. The corresponding investigations confirm the presence of TaSi2 compound. Quantitative analyses indicate the atom ratio of Ta and Si is 1:2.2 utilizing integral peak area sensitivity factor method,which is close to that of stoichiometry TaSi2. The further analysis demonstrates that the formation of TaC is due to the reaction of Ta element and C in the laser ablation process,and the formation of SiC is due to the reaction of Si with C. At the same time,most of the O signals come from the chemical adsorption oxygen on the surface composition of TaSi2 nanoparticles.