Objective To investigate the value of long-term nutritional monitoring for prognosis of maintenance hemodialysis (MHD) patients.  Methods A single-center, retrospective and cohort study was conducted, enrolling 113 MHD patients who received regular nutritional monitoring at our center in June 2015 and were followed up until July 2022. Baseline demographic characteristics, laboratory results, and cause of death were collected. Nutritional monitoring included serum albumin measurement, subjective global assessment (SGA), anthropometric measurements (mid-upper arm circumference, triceps skinfold thickness, mid-upper arm muscle circumference), and handgrip strength assessment. The endpoint was all-cause mortality. Logistic regression analysis was used to examine the relationship between nutritional indicators and prognosis.  Results During follow-up, 48 patients died primarily due to cardiovascular events (60.4%), cerebrovascular accidents (16.7%), and infections (8.3%). The proportion of patients with a final SGA score of grade A in the survival group was significantly higher than that in the death group, and the difference between the two groups was statistically significant (χ²=15.89, P<0.001). Multivariate logistic regression analysis showed that age (OR=1.044, 95% CI: 1.007～1.082, P=0.018), baseline serum creatinine (OR=0.998, 95% CI: 0.996～1.000, P=0.042), and baseline serum magnesium (OR=0.035, 95% CI: 0.001～0.968, P=0.048) were the independent predictors of all-cause mortality in MHD patients. The independent risk factors for death within 5 years in follow-up period were serum creatinine (OR=0.997, 95% CI: 0.995～0.999, P=0.003) and arm muscle circumference (OR=0.792, 95% CI: 0.574～0.977, P=0.023).  Conclusion  Long-term and regular comprehensive nutritional monitoring contributes to a predictive value for prognosis in MHD patients. SGA score id helpful to identify the patients with high risk of recent mortality, while upper arm circumference serves as a key indicator for predicting long-term prognosis.