The ethylene (C2H4)and acetylene (C2H2)co-adsorbed with K on Ru(1010)surface has been studied by using ultraviolet spectroscopy(UPS).The results show that ethylene (C2H4) is absorbed in molecular state on Ru(1010)surface stably below 200 K.The dehydrogenated of ethylene occurs at 200 K.The main product of the dehydrogenation of the absorbed ethylene (C2H4)is the acetylene (C2H2).After the dehydrogenation of the absorbed ethylene(C2H4),the binding energies of σCC and σCH bonds have an increase of 0.2 eV and 0.5 eV respectively.The acetylene is absorbed in molecular state on Ru(1010)surface stably at room temperature.On a K pre-covered surface,the σCC peak disappears at room temperature.The element K promotes the dissociation of acetylene on Ru(1010)surface.