In 1996~1997 a joint trial of cotton double cropping was conducted at 5 sites in Huanghuaihai plains.In each side, main treatmment are 2 planting patterns and subplots and 4 wheat/cotton variety combinations with 4×4 latin square design. The results showed that wheat cotton double cropping had a high productivity and economic benefits. The wheat yield/year was 4491 kg/ha, cotton yield 1299 kg/ha, prefrost lint ratio 90%,and the net output reached 167466 yuan(RMB)/ha. The wheat productivity in the northern plains under wheat cotton double cropping exceeded that in the southern plains by 8.6%, and the productivity of the intercropped cotton was lower by 27.6%. As a result the net output /year round lowered by 28.7%. In comparison with the 4 2 planting pattern, the wheat yield in 3 2 planting pattern decreased by 3.7%, the cotton yield increased by 5.7%, and a net output incerment of 7.6% was ensured. The factors contributed to high productivity included: the intercropping of wheat and cotton, the suitable planting pattern, the tolerant late sown and dwarf wheat variety with a compact plant type, the mid early mature cotton variety and the transplanting of cotton seedling or the direct sowing mulched film, or the short season cotton variety and early intercropping. In 1996 ~ 1997 a joint trial of cotton double cropping was conducted at 5 sites in Huanghuaihai plains.In each side, main treatmment are 2 planting patterns and subplots and 4 wheat / cotton variety combinations with 4 × 4 latin square design. The results showed that wheat cotton double cropping had a high productivity and economic benefits. The wheat yield / year was 4491 kg / ha, cotton yield 1299 kg / ha, prefrost lint ratio 90%, and the net output reached 167466 yuan (RMB) / ha. The wheat productivity in the northern plains under wheat cotton double cropping exceeded that in the southern plains by 8.6%, and the productivity of the intercropped cotton was lower by 27.6%. As a result the net output / comparison with the 4 2 planting pattern, the wheat yield in 3 2 planting pattern decreased by 3.7%, the cotton yield increased by 5.7%, and a net output incerment of 7.6% was ensured. The factors contributing to high productivity included: the intercropping of wheat a nd cotton, the suitable planting pattern, the tolerant late sown and dwarf wheat variety with a compact plant type, the mid early mature cotton variety and the transplanting of cotton seedling or the direct sowing mulched film, or the short season cotton variety and early intercropping .