This paper is concerned with a planar Schr & ouml;dinger-Poisson system involving Stein-Weiss nonlinearity {-Delta u+V(x)u+phi u=1|x|beta(integral(RF)-F-2(u(y))|x-y|mu|y|beta dy)f(u),x is an element of R-2, Delta phi=u(2),x is an element of R-2,(0.1) and its degenerate case {-Delta u+phi u=(integral(RF)-F-2(u(y))|x-y|mu dy)f(u),x is an element of R-2, Delta phi=u(2),x is an element of R2,(0.2) where beta >= 0, 0<mu<2, 2 beta+mu<2,V is an element of C(R2,R) and f is of exponential critical growth. By combining variational methods, Stein-Weiss inequality and somedelicate analysis, we derive the existence of ground state solution for the first system.Under some mild assumptions, we introduce the Pohozaev identity of the equivalent equation of the second system and use Jeanjean's monotonicity method to achieve the existence of nontrivial solution for the second system.