The potential threshold for dietary energy intake (DEI) that might prevent protein-energy wasting (PEW) in chronic kidney disease (CKD) is uncertain. The subjects were non-dialysis CKD patients aged >= 14 years who were hospitalised from September 2019 to July 2022. PEW was measured by subjective global assessment. DEI and dietary protein intake (DPI) were obtained by 3-d diet recalls. Patients were divided into adequate DEI group and inadequate DEI group according to DEI >= 30 or < 30 kcal/kg/d. Logistic regression analysis and restricted cubic spline were used in this study. We enrolled 409 patients, with 53<middle dot>8 % had hypertension and 18<middle dot>6 % had diabetes. The DEI and DPI were 27<middle dot>63 (sd 5<middle dot>79) kcal/kg/d and 1<middle dot>00 (0<middle dot>90, 1<middle dot>20) g/kg/d, respectively. 69<middle dot>2 % of participants are in the inadequate DEI group. Malnutrition occurred in 18<middle dot>6 % of patients. Comparing with patients in the adequate DEI group, those in the inadequate DEI group had significantly lower total lymphocyte count, serum cholesterol and LDL-cholesterol and a higher prevalence of PEW. For every 1 kcal/kg/d increase in DEI, the incidence of PEW was reduced by 12<middle dot>0 % (OR: 0<middle dot>880, 95 % CI: 0<middle dot>830, 0<middle dot>933, P < 0<middle dot>001). There was a nonlinear curve relationship between DEI and PEW (overall P < 0<middle dot>001), and DEI >= 27<middle dot>6 kcal/kg/d may have a preventive effect on PEW in CKD. Low DPI was also significantly associated with malnutrition, but not when DEI was adequate. Decreased energy intake may be a more important factor of PEW in CKD than protein intake.