This brief proposes a continuous output feedback terminal sliding mode (TSM) control method for the output tracking problem of nonlinear systems with mismatched uncertainties. This method is developed by two consecutive steps: 1) design a sliding mode observer to estimate the derivative and high-order derivatives of system output and 2) construct a continuous TSM controller based on system output and the estimations of its high-order derivatives. The proposed controller not only guarantees system output converges to its reference in finite time but also keeps the continuity of control action. Experiments on single-phase dc-ac inverter circuits are also carried out to show the effectiveness of the proposed controller.