Objective To determine the relationship between zinc and nutritional status or immunity in patients with end-stage renal disease undergoing continuous ambulatory peritoneal dialysis (CAPD). Methods Forty-five stable CAPD patients undergoing peritoneal dialysis were enrolled in this study. The dietary zinc intake and serum zinc levels were investigated, and the results were compared with the gender- and age-matched healthy populations (n = 45). The relationship between dietary zinc intake and serum zinc levels and subjective global assessment (SGA) score, blood cell counts, serum albumin (ALB), prealbumin (PA), C-reactive protein (CRP),and lymphocyte subsets were analyzed. Results The percentages of inadequate dietary zinc intake (P= 0. 007)and low blood zinc (P = 0. 036) were significantly higher in CAPD patients than in healthy group. CD8 levels were significantly lower (P = 0. 000) while CD4/CD8 ratio was significantly higher (P = 0. 033) in CAPD patients than in healthy group. In CAPD patients, correlation analysis showed that dietary zinc intake was significantly correlated with serum prealbumin levels (r = 0. 577, P = 0. 000), but was negatively correlated with SGA score (r = - 0.354,P = 0. 015) and CRP (r = - 0.354, P = 0. 015); however, it was not significantly correlated with lymphocyte subsets and CD4/CD8 ratio. Serum zinc level was significantly positively correlated with hemoglobin (r= 0. 411, P=0.005), hematocrit (r=0.345, P=0.023), WBC (r=0.318, P=0.035), SGA score (r=0.417, P=0. 005), and CRP (r=0.342, P = 0. 027), but was not significantly correlated with lymphocyte subsets and CD4/CD8 ratio. Conclusions Zinc deficiency is common among patients with CAPD. Adequate dietary zinc intake can facilitate protein synthesis and improve the overall nutritional status. High serum zinc concentrations are beneficial for the synthesis of hemoglobin and the improvement of anemia.