—This study investigated the developmental changes of perceptual and cognitive commonsense physical knowledge. Children 4 to 9 years old (N = 156; 79 boys, 77 girls) participated. Each child was asked to predict the landing positions of balls that rolled down and fell off a virtual ramp and to choose the most naturallooking motion from different projectile motions depicted. The landing position of the most natural-looking projectile was compared with the predicted landing position and also compared with the actual landing position. The results showed children predicted the ball's landing position closer to the ramp than the actual position. Children also chose the depiction in which the ball fell closer to the ramp than the accurate position, although the error in the prediction task was larger than in the perception task and decreased with age. The results indicated the developmental convergence of explicit reasoning and implicit perception, which suggest a single knowledge system with representational re-description.