Abstract: Until now, multiple linear cryptanalysis proposed by B.S.Kaliski and M.J.B.Robshaw has not been realized by multiple linear approximation equations, The paper selects eight different start points in linear combinational pass chain which period is eight and is constructed by Mastui. This linear combinational pass chain constructs eight new chains, then plus its dual chains, gets totally sixteen chains; finally, key bits of DES can be attacked by these chains.