Abstract: This experiment studied the tomato population structure in the film greenhouse and its light distributon characteristic under the different density conditions. The results showed that the most suitable density of the tomato elevated culture in the plastic film greenhouse was 556 plants / m², and its spacing in the rows and row distance were 30 × 60cm. The highest yield of the tomato cultured under the above density during the middle-earty stage before August 10 was 5940kg / mu. Its most suitable physiological in dices were as follows. The leaf area density(LTD) of the coown layer was 0.942 m²/m². The leaf capacity was 98.6 pieces / m². The received radiation amoumt at the crown layer was 45.6% . The received photon amount at the crown layer was 40.3%. The relative light degree within the crown layer was 38.5%. The extinction coefficient of the population was 1.04.