Wings are the main source of lift for the underwater gliders (UGs), and play a decisive role in the motion performance of UGs. A lab-scale UG with flexible camber trailing edge wings was proposed and developed to investigate influences of the trailing edge of the wings on the motion performance of UGs. The flexible deformation of the trailing edge was realized by the steer-by-wire actuator. Test results showed that the trailing edge of the wing can realize the maximum upward/downward sloping angles of +16°/-16°. Combining computational fluid dynamics simulations and tank experiments, the glide efficiency and stable margins of the lab-scale UG with variable camber trailing edge wings were obtained. Results showed that the angles of attack corresponding to the minimum lift-to-drag ratios were all negative in cases of downward sloping, and those were all positive in cases of upward sloping. Moreover, the suitable camber of the trailing edge, i.e., downward-sloping trailing edge on descending glides and upward-sloping trailing edge on ascending glides, can not only greatly improve glide efficiency, but also benefit the flight stability. The lift-to-drag ratios of the lab-scale UG with appropriate variable camber trailing edge wings (i.e., on descending glide with downward-sloping trailing edge, and on ascending glide with upward-sloping trialing edge) can increase by at least 10% compared with those with symmetric airfoil.