Berberine is an isoquinoline alkaloid found in some plants and has many bioactivities including anti-microbial, lipid- and glucose-lowering, anti-cancer, anti-inflammatory, etc. However, there is limited knowledge about berberine’s effects on development and locomotive activity. Herein, in vivo studies were conducted to determine these effects of berberine using Caenorhabditis elegans as an in vivo model. Treatment of berberine at 50 μM starting at L1 stage significantly retarded the growth rate of nematodes, and reduced the length, width and moving speed of worms by 19%, 12% and 29%, respectively, compared to the control. In addition, triglycerides (TG) and protein content in worms was reduced by 23% and 28%, respectively, after berberine treatment from L1 stage compared with the control group. However, no significance was observed when berberine was treated from young adult stage. These findings suggest that berberine has effects on development in C. elegans.