The application of Azolla-based liquid biofertilizer is a fertilizer supplement for vegetable crops that utilizes the natural potential around agricultural land. Various studies reveal that the concentration of liquid biofertilizer application varies so that for the efficient use of liquid biofertilizer it is necessary to find the right concentration. The purpose of this study was to analyze the response of pakcoy plants through the application of different concentrations of biofertilizers to increase the growth and yield of pakcoy plants. This study used seven treatments with six replications arranged according to a randomized block design. The experimental treatments consisted of: without giving biofertilizers (K0), 5 ml l -1 biofertilizers (K1), 10 ml l -1 biofertilizers (K2), 15 ml l -1 biolofertilizers (K3), 20 ml l -1 biofertilizers (K4), 25 ml l -1 biofertilizer (K5), 30 ml l -1 biofertilizer (K6). The results showed that concentrations of biofertilizers ranging from 5 to 30 ml/l could increase plant height, number of leaves, leaf width, leaf length, and leaf area and fresh weight of pakcoy plants compared to no application of biofertilizers. The concentration of 10 ml l -1 biofertilizer resulted in a higher number of pakcoy leaves than the control but did not differ from the fresh weight of the pakcoy plant at each concentration of biofertilizer given. The application of biofertilizer with a concentration of 10 ml l -1 increased the fresh weight of pakcoy plants twice or 100.74% compared to the control. Azolla-based liquid biolofertilizers can be used as additional nutrients for NPK fertilizers to increase the growth and yield of pakcoy plants.