By using the variational method and critical point theory

especially critical group and Morse theory

combined with the matrix theory and space dimension

taking into account the critical points of both positive and negative energy functional

the multiplicity of solutions of 1-dimensional nonlinear discrete elliptic resonant problem was investigated.Under some assumptions

two kinds of new sufficient conditions were obtained under which there exist at least two nonzero solutions.An example was given to verify the obtained results.The results showed that

under the same assumptions

the number of known solutions of 1-dimensional resonant problem is more than that of multidimensional resonant problem.