Immature coffee beans are known to adversely affect the coffee beverage quality and thus new attempts are being sought for their utilization. Studies have shown that such beans contain larger amounts of phenolics, mainly chlorogenic acids, in comparison to mature coffee beans. Thus, in this study, we evaluated the potential of immature coffee beans as substrate for the production of fibers. Wheat bran was used as a reference. Immature (IF) and mature (MF) green coffee beans were blanched (hot water - 90oC - followed by cold water - 4oC, 3 min each), ground, dried (50oC for 6h) and sieved through a 425-μm mesh. Commercially available wheat bran was dried and ground to the same conditions (WF). An enzymatic–gravimetric method was used to determine the total dietary fiber content. In vitro antioxidant capacity was evaluated by reaction with 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS). Total dietary fiber contents ranged from 53.2 to 53.6% for IF and MF in comparison to 45.8% for WF. IF and WF presented higher soluble fiber content (3.6%) in comparison to MF (2.8%). In vitro antioxidant activity was slightly higher for IF (2.7 µM TE/g) in comparison to MF (2.4 µM TE/g), but lower that WF (6.2 µM TE/g). Desired technological properties for use of the IF as food ingredient, including water solubility (18%), oil retention capacity (1.5 g/g), water retention capacity (2 g/g), and swelling capacity (3.3 mL/g) within the food industry applicable range indicate that immature coffees can be viewed an interesting source of dietary fibers.