The field experiment s which included dif ferent rotations w ere conducted in different ecolog ical condition(Heihe and Hailun)to study the ef fect s of soybean cropping of cont inuous and alternating wi th another cropon the content of protein , oil and the total content of pro tein &oil .The results showed that in different experimentsites the effect of alternating cropping w ith another crop on the content of protein and the total of protein&oil w as irregular .The soybean cropping of alternating w ith another crop entanced the content of oil slight ly ,and the increasing extent s of different ro tatio n pat tern w ere dif ferent .In a sho rt period (about 2 years)the effectof continuos cropping on the content of oil was not regular .The continuous soybean cropping increased thecontent of protein and the increased ex tent turnde bigger as years of continuous cropping ex tended .Af ter 3 yearsthe content of oil w ent lower by soy bean continuos cropping , and the decreasing extent increased w ith the yearsof continuous cropping extending .The soybean continuos cropping increased the total of pro tein & oil and theentent grow as years of continuos cropping extended(af ter 2years of soy bean continuous cropping).