Objective: Increasing viscous dietary fiber in snacks may have several nutritional advantages, especially for adolescents. Having a snack that may exert direct health benefits and that may, at the same time, contribute to the voluntary reduction of energy intake through modulation of appetite may be a useful dietary strategy for energy control in adolescence. In this short-term study, a new type of biscuit containing 5.2% barley beta-glucan was produced and its effect on appetite moods and food intake was investigated. Methods: Twenty healthy adolescents were selected and randomly assigned to receive, as a midmorning snack, a 628 kJ (SP) or 1884 kJ (LP) preload of barley beta-glucan enriched (BB) or control (CB) biscuits. Appetite ratings before and within 2 hours following the snack, as well as the energy intake at lunch, were recorded. Results: For all sensations, a peak at 15 minutes post-snack and a subsequent return to baseline value were shown. A decrease of the area under the curve (AUC) of the desire to eat and an increase of the AUC of fullness and satiety were recorded with SP-BB compared to SP-CB. The energy intake recorded at the lunch test was always significantly lower than that at the control lunch only in females (3048 kJ vs. 3890 kJ) independently from the type of snack consumed. Total energy intake significantly correlated with preload values both in females and in males, but not with the type of biscuit. Nutritional composition of meals consumed ad libitum did not vary significantly from those with different preloads. Conclusions: The BB, consumed as a midmorning snack, although able to influence appetite ratings, did not modify food intake in a short time period.