  Based on the quantum superspace construction of $q$-deformed algebra, we
discuss a supersymmetric extension of the deformed Virasoro algebra, which is a
subset of the $q$-$W_{\infty}$ algebra recently appeared in the context of
two-dimensional string theory. We analyze two types of deformed super-Virasoro
algebra as well as their $osp(1,2)$ subalgebras. Applying our quantum
superspace structure to conformal field theory, we find the same type of
deformation of affine $sl(2)$ algebra.
