The aim of this study was to determine the impact of Bacillus subtilis supplementation on body weight and body dimensions in Noi chickens from 63-91 days old. A total of 48 broilers (4 male or female birds per pen) were subjected to two treatments wherein half of them (12 males and 12 females) was given ad libitum GF1324 commercial feed produced by GreenFeed Vietnam Joint Stock Company and provided clean water, while the remainders were fed ad libitum GF1324 and supplied Bacillus subtilis water (0.5g Bacillus subtilis with ≥1011 spores/g diluted with 5 litters of water) for three times per week during the experiment.Our results indicated that addition of Bacillus subtilis may improve body weight, back length, and breast diameter at various time points of age in Noi broilers. However, a supplementation of Bacillus subtilis with higher concentration should be considered in further studies in whichimportant economic traits such as back length, breast diameter and thigh diameter could be revealed clearer.