The fruit of Rubus nubigenus has about 200 drupelets joined to a central torus, which is white. The pyrene is found within each drupelet and is surrounded by pulp. The pulp is juicy and sweet to sour, depending on the maturity of the fruit. Each dupelet has a carpel, which is dry and remains attached. The drupelets also bear pubescences. The author found that the mean fruit weight, length, and width were 10.83 g, 32.83 mm, and 24.93 mm, respectively. Rubus nubigenus is predated by vertebrates. The mean pyrene weight, length, and width were 4.75 mg, 3.85 mm, and 2.02 mm, respectively. The pyrene coat ultrastructure of R. nubigenus is characterized by rounded cell outlines. The pyrene coat sculpturing has ridges and lower parts or valleys. The ridges form a connected structure and surround the lower valleys.