Abstract: In DNA arithmetic computation the residue number system defined by 4-moduli set is introduced,in which the arithmetic computation can be performed in parallel and the scheme of DNA encoding in practice can be simplified,thus decreasing the complexity of the algorithm.The principle of the residue number system and the computational model are analyzed firstly.Then the encoding scheme of DNA representation of integers with modular representation is presented,and the concrete procedure of DNA residue arithmetic computation is proposed.Finally,the complexity of the algorithm and the encoding in DNA residue arithmetic computation is discussed.