The process of rice seedlings passing through the separating chutes was observed using high speed photography technology. The circular arc part of chutes was the key that affects the rice seedlings passing through chutes. It was easier for rice seedlings to pass chute No.4~7 than No.1~3. The time of rice seedlings passing through chutes was shorter and closed to simulation results calculated by computer when water content of nutrient soil of rice seedlings was 26.6%. It need the longest time when rice seedlings pass through chute No.1. The shortest time appeared when rice seedlings passing through chute No.6. The results of experiment showed that chutes of separating rice seedlings could be satisfied the requirements of throwing transplant machine for rice seedlings sprouted in the plastic cell-tray. 