Abstract: Robust stabilization for a class of uncertain nonlinear singular systems with the norm-bounded condition is studied. The methods for robust stabilization of uncertain non-singular nonlinear systems are extended to singular systems. The concept of robust stabilization is defined in the sense of Lyapunov. A necessary and sufficient condition under which the systems are robustly stabilizable is obtained. Under the norm-bounded condition the robust stabilizability of uncertain nonlinear singular systems is shown to be equivalent to the existence of a positive solution of an extended Hamilton-Jacobi-Isaacs differential inequality.