Abstract: This paper introduced wide application and devehpment of DPC regulation measure in cotton cultural technological system in Guan zhong cotton section since 1983 year to 2001 year. According to statistical data, the exploited rate of DPC and the accumulated application areas of DPC reached to 90% at present from past 65% and 112.7×104hm2. Mean yield and Lint increased by 12.1% and 8126×103kg, total profit and the ratio expenditure to profit reached to ￥8.16×108 and 1 divided by 25 to 40. The statistical data indicated that whenever DPC regulation measure was applied in cotton planting, it could all increased yield, However, optimum used duration of DPC regulation measure was following: firstly, DPC, 7.5g to 12g per hm2, was sprayed when cotton grew into 7 leaves or 8 leaves; secondly DPC, 22.5g to 37.5g per hm2, when cotton 15 leaves or 16 leaves; finally, DPC, 45g to 75g per hm2, when tenth days that the most top of cotton tree was cut. The reasons why DPC regulation measure could increase yield had many factors. It could descend down plant height from 100cm to 85cm and make densities increase form 4000 plants to 9×104 to 9.7×104 plants. So cotton bolls increased 9.1%. on the basis of data analysed, the author put forward the important faction of the technology of DPC regulation measure combined with tradition agronomic cultural technologies.