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The rain-fed maize was selected as the research object. Three typical chemical agents(Polyacrylamide, Superabsorbent polymer and Fulvic acid) were combined to apply on maize production. The effects of chemical integrated control technology on the soil water, nitrogen and maize yield were researched, and the optimal chemical integrated application pattern was explored. The results indicated that the effect of three chemical agents on soil water, nitrogen and maize yield was inconsistent. PAM and SAP had significant effect on soil water and available nitrogen, while PAM, SAP and FA were combined to have effect on total nitrogen and maize yield. The largest maize yield was gotten with FA 400 times liquid and SAP 90 kg/hm2 with 270 kg/hm2 urea application, meanwhile, the available nitrogen and average soil water were 5.44 mg/kg and 0.12 respectively, which were bigger than any other experimental treatment. The higher soil water and available nitrogen were beneficial for plant to uptake water and nitrogen. Compared with the treatment without chemical agents, the maximize improvement for maize yield could be able to 21% after chemical integrated control technology application. 