In a Gray code over Gaussian integer vectors, two words differ in one position by 1,-1, i or -i, where i = sqrt{-1}.  Similarly in a Gray code over EJ integer vectors, two words differ in one position by pm 1, pm rho, pm rho ^ {2}, where rho = (1 + sqrt{3} i)/2.  In this talk, some Gray codes over these integer vectors are designed. How to construct edge disjoint Hamiltonian cycles in Gaussian and EJ graphs are also described.