Biofloc technology (BFT) was widely applied as a sustainable tool for use in aquaculture that simultaneously addresses environmental, social, and economic issues. This study aimed to evaluate the effects of carbon addition time on water quality, biofloc compositions, and Litopenaeus vannamei larvae performance. The experiment was conducted with four carbon addition times at Mysis-1 (Treatment 1), Mysis-3 (Treatment 2), Postlarvae-2 (PL-2) (Treatment 3) and Postlarvae-4 (PL-4) stage (Treatment 4). The larvae were stoked in 500L composite tanks at 30 ppt of salinity and 150 ind L-1 of density. According to the experimental designed treatments, refined sugar was daily applied as a carbon source to maintain the C/N ratio at 20:1. The results showed that the water quality, total bacteria and Vibrio spp. count, and biofloc performance in all treatments were in an appropriate range for larvae development. The treatment 2 (Mysis-3) was recorded with the highest growth, survival and productivity of PL-12 (10.47±0.12 mm, 66.5±5.5%, 99,709±8,231 ind m-3, respectively), which were significantly different compared to others (p < 0.05). All the postlarvae-12 survived after formalin and salinity shock tests. These results suggested that sugar could be applied for white leg shrimp larvae rearing at Mysis-3 stage to promote the biofloc development, water quality management and larval performance.