In this article, we study the existence and nonexistence results of positive weak solutions for semilinear elliptic system of the form:where λ is a positive parameter, α,β ∈ (0, 1) and Ω ⊂ R n (n > 1) is a bounded domain with smooth boundary ∂Ω. Here f, g are C 1 non-decreasing functions such that f , g:) > 0 for u, v > 0 and a(x), b(x) are C 1 sign-changing functions that are probably negative near the boundary. In particular, on f (0, 0) or g(0, 0) there is no any sign conditions. Our approach is based on the sub-super solutions method. Also, under some certain conditions, we study the stability and instability properties of the positive weak solution for the system under consideration.