There are provided a method for constructing a permutation matrix or a check matrix, a processing device, a storage medium and a coding method. The method of constructing a permutation matrix includes: obtaining a base matrix used for the permutation matrix; and lifting the base matrix to obtain the permutation matrix, which includes: obtaining a protograph of the base matrix; and obtaining each macro-cycle in the protograph, and for each macro-cycle in the protograph, determining a size of a short cycle corresponding to the macro-cycle in a Tanner graph of the check matrix corresponding to the permutation matrix by an equivalent cyclic value ECS of the macro-cycle, and determining whether at least one cyclic value in the macro-cycle needs to be set according to the size of the short cycle. The method can efficiently obtain the permutation matrix as required.