This study examines the effects of varying LED durations and the seedling’s dark phase on microgreen mung bean growth rate, yield, and quality. Conducted in December 2023 at the Laboratory of Microgreen Cultivation, Jl. Joyo Agung, Malang, at an elevation of approximately 625 meters, the study utilized a box experiment with a split-plot design. The primary variable was the length of the LED dark phase (0, 12, and 18 hours), while the subplot focused on the early seedling dark phase treatment (two 24-hour dark phases and no dark phase). Analysis of variance showed no significant interaction between LED exposure time and blackout treatment, except for plant texture. The best plant texture (6.10 mm/s) was achieved with 18 hours of exposure and an early-stage dark period. LED light exposure influenced the total fresh weight, total dry weight, and total soluble solids of the plants. The 12-hour exposure produced the highest total fresh weight (85.15 g), while the 18-hour exposure resulted in the highest total dry weight (6.28 g), crown dry weight (5.70 g), and total soluble solids at 4 and 6 days after sowing (8.80oBrix and 8.27oBrix, respectively).