This study was conducted to investigate the effects of lysine (Lys), methionine (Met) and threonine (Thr) supplementation on growth performance and serum biochemical parameters of calves. Twenty-four neonatal Holstein calves were selected and assigned randomly to 4 treatments according to the body weight and date of birth. The study lasted for 8 weeks. Four amino acids models in milk replacers (MR) were applied in each treatment, which were consisted of balanced amino acids model (PC group), Lys, Met and Thr deduction models (PC-Lys, PC-Met and PC-Thr group, repectively). The deduction levels were all 30% of PC group. The results showed as follows: 1) compared to the deduction models, calves fed with balanced amino acids model significantly decreased the feed to gain ratio (P<0.05), significantly increased the average daily gain aged from 2 to 4 weeks (P<0.05), and significantly increased the thorax girth change ratio and body oblique length change ratio aged from 0 to 2 weeks (P<0.05); 2) compared to the deduction models, calves fed with balanced amino acids model significantly increase the serum albumin content aged from 0 to 8 weeks and at 8 weeks old (P<0.05), significantly decreased serum globulin content at 8 weeks old (P<0.05), but significantly increased serum glucose aged from 0 to 8 weeks (P<0.05);3) with the growing of calves, serum total protein increased, serum glucose increased at first and then decreased. In conclusion, the partial deductions of Lys, Met and Thr have negative effects on growth performance and serum biochemical parameters of calves.［Chinese Journal of Animal Nutrition，2011，23（2）：226-233］