This experiment was conducted to investigate the changes of rate of infected common scab and yield characteristics of fall patato(Solanum tuberosum L.) where green manual crops had been previously cultivated, crushed and tilled and PㆍE transparent vinyl film had been mulched and tunneled to solar heating of soil from May 21. 1998 to July 28. 1998. The total yields of green manual crops which had been previousely cultivated were as followed order ： pioneer 855F(64.3MT/ha), soybean(25.0MT/ha), red clover and orchardgrass. The average below-ground temperature at the depths of 5, 10 and 20cm were 54, 45 and 4 4V during the mulching period, respectively. The rate of infected area per potato tuber of common scab decreased by solar heating the soils with mulching after the soybean and red clover cultivation as with previous croppings. Plant height, SPAD(soil plant analysis development) reading, fresh weight of steins, and fall potato's tuber yields tended to increase by the cultivation of green manual crops and mulching of PㆍE film. Fall potato's tuber yields were remarkably affected in the plot of soybean, red clover and pioneer 855F+cultivation of fall potato. T-N, K and Ca contents of fall potato(stem and tuber) also tended to increase by the cultivation of green manual crops and mulching of PㆍE film. T-N, K and Ca contents of soil tended to increase after the cultivation of green manual crops and mulching of PㆍE film and then reduced to contents of soil before green manual planting after potato harvesting.