This study was designed to evaluate the requirements of sodium and chlorine for Jinding laying ducks aged from 5 to 11 weeks. Nine hundred and sixty Jinding ducks were chosen and randomly divided into 8 groups according to the body weight with 10 replicates of 12 ducks per replicate which were fed diets with sodium chloride of 0, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.48% and 0.96% in the basal diet (contained 0.037% sodium, 0.047% chlorine and 0.710% kalium), respectively. The trial lasted for 7 weeks. The results showed that sodium chloride significantly affected average daily weight gain (ADG), average daily feed intake (ADFI) and the ratio of feed to gain (F/G) of growth laying ducks (P<0.05). The contents of CO2 and pH in serum were decreased as the supplemental level of sodium chloride increased (P>0.05). The content of bicarbonate ion was decreased as the supplemental level of sodium chloride increased. The anion gap was lower when supplemented with 0 sodium chloride than that supplemented with 0.20%-0.96% sodium chloride (P<0.05). The osmotic pressure was increased as the level of sodium chloride increased and there were significantly differences between 0 and 0.96% sodium chloride adding groups. The sodium and chlorine had no significant effect on the content of triglyceride and total cholesterol (P>0.05), but significantly affected the contents of urea nitrogen and glucose in serum (P<0.05). It was concluded that the diet supplemented with 0.24% sodium chloride which contained 0.131% sodium and 0.193% chlorine could meet the requirement of 5 to 11 weeks Jinding laying ducks in production.［Chinese Journal of Animal Nutrition, 2010，22（2）:460-465］