Abstract: Mini watermelon variety ‘Chuanqi -4’was used to study the effects on growth cycle, quality, and yield of different plant density, the experiment was carried out by randomized blocks design. have 4 Experimental treatments，planting distance 42 cm conventional planting density is control group。The results showed that the, growth cycle and quality of different plant density has not obvious on the mini watermelon variety ‘Chuanqi -4’ ; 36 cm plant density Significantly improved the yield, increase of about 11% than the control group。So Hanging single tendril cultivation in the fall of plastic greenhouses, the suitable planting density was 1852 plants/667m2, use one vine with one fruit.