The ethylene (C2H4) adsorbed on Ru(1010) surface has been studied by X-ray photoelectron spectroscopy (XPS),thermal desorption spectroscop y (TDS) and ultraviolet photoelectron spectroscopy (UPS).The results show that e thylene absorbs in molecular state on Ru(1010) surface stably below 200K.The deh ydrogenation of ethylene occurs at 200K.The main product of the dehydrogenation of the absorbed ethylene is the acetylene (C2H2). After th e dehydrogenation of the absorbed ethylene,the C1s shifts 0.3eV to low binding e nergy level,and the binding energies of σCC and σCH bond have an increase of 0.5eV and 1.1eV respectively.