A single-cavity toroidal continuously variable transmission capable of suppressing gyro slippage and achieving mitigation of bearing loss and a longer service life. A pitch circle diameter (PCD) of the output-side bearing is smaller than that of the input-side bearing and a ball diameter of the output-side bearing is smaller than that of the input-side bearing. Therefore, centrifugal force acting on the ball of the output-side bearing on a speed increasing side with a low load can be suppressed. Therefore, gyro slippage can be suppressed and mitigation of bearing loss can be achieved. Furthermore, with a groove R ratio of the output-side bearing smaller than that of the input-side bearing, a longer service life can be achieved even when the pitch circle diameter (PCD) and ball diameter of the output-side bearing are smaller than those of the input-side bearing.