Objective. To improve and ensure the quality of nursing (QOC), scientifically and effectively improve nursing management, and improve the hospital QOC overall level and construction of nursing quality evaluation index suitable for China (NQEI) system. Method. This research is based on the fuzzy neural network (FNN) big data analysis technology, and temperature of hospital patients,blood pressure, blood sugar, blood uric acid, and other data were analyzed, assisted by health big data NQEI. With this, in smart medicine (WIT120), under the background of big data assisted analysis NQEI system and the nursing satisfaction index of patients, inpatient management index, quality of inpatient management, and quality of inpatient management, the coupling of four aspects is analyzed. Result. The results showed that, in the coupling analysis of nursing satisfaction indicators, using the big data assisted NQEI system, the comprehensive satisfaction of patients with nursing was 0.963, and the complaint rate is −0.963. In the coupling analysis of patient hospitalization management indicators, assisted by big data NQEI, the average length of stay of patients in the system is −0.982, postoperative recovery time is −0.996, and ICU time is −0.892. In the coupling analysis of patient hospitalization management quality, assisted by big data assisted NQEI, the inpatient infection of the system is −0.982, the postoperative rehabilitation time was −0.996, and the ICU time was −0.892. In the coupling analysis of patient prognosis management quality, assisted by big data assisted NQEI, the re-examination compliance rate of patients in the system is 0.997, and the medication compliance rate is 0.995, indicating that it is assisted by the big data NQEI system and has high correlation with real data. Conclusion. Through analysis, it is proved that using big data to assist the NQEI system, patients’ nursing satisfaction index, inpatient management index, inpatient management quality, and inpatient management quality are better than those using the quality control circle NQEI high system, and the results are credible. However, its clinical application is not perfect and needs further verification.