A novel high-yield variety of Grifola frondosa(maitake)—Damhyang—was developed by Gangwon Agricultural Research and Extension Services to enhance productivity and broaden utilization. The optimal conditions for mycelial culture, fruiting initiation, and growth were approximately 25, 20, and 18 °C, respectively, comparable to those of the control variety. Morphological characteristics were examined, and yield performance was assessed through productivity tests and farm validation trials. Damhyang exhibited distinctive traits, including upward-facing pileus margins and lightgray pileus color, differentiating it from the control. The appropriate incubation period was 70 days, with maturity reached after approximately 20 days after bag cutting, slightly later than that of the control. Despite the longer harvest period, yield increased by 12 % in the productivity tests and 16 % in the farm trials. The superior yield was attributed to the upwardoriented pileus margins; elongated clusters; and larger, thicker, and denser pileus. Compared with the previous highyielding variety (Dami), Damhyang exhibited significantly higher productivity. Damhyang is expected to be widely adopted as an edible mushroom and is a promising candidate for processing applications.