Caffeine is a heavily consumed substance that has several benefits, including appetite suppression and increased energy metabolism. PURPOSE: To determine the effect of caffeine amount and coffee volume on appetite profile, affective response, cognitive function, blood glucose levels and subsequent energy intake in female habitual caffeine consumers. METHODS: 19 healthy female (age: 24 ± 8, BF%: 24.9 ± 5.1) habitual caffeine consumers (255 ± 122 mg/day) ingested coffee of different volumes and caffeine amounts on four different occasions (C1: 237 ml/4 mg/kg; C2: 237 ml/6mg/kg; C3: 473 ml/4mg/kg; C4: 473 ml/6mg/kg) in a single blind, randomized, crossover design. Participants completed a visual analog scale (VAS) of appetite profile at pre, 0, 30 and 60 minutes. Affective response and cognitive function were assessed using the Activation-Deactivation Adjective Checklist (AD-ACL), Trail Making (TM) and Stroop tasks (ST) before and after the test drink. Blood glucose levels were measured at pre, 30 and 60 minutes. In addition, ad libitum breakfast was consumed at 60 minutes and 24-hour self-reported energy intake was recorded. A repeated measures ANOVA was used for analysis with significance accepted at p<0.05. RESULTS: A significant time (p<0.001), but not condition effect was observed in hunger (p=0.31), satiety (p=0.16), fullness (p=0.11), desire to eat (p=0.31) and prospective food consumption (p=0.19). No significant condition effect was observed in blood glucose levels (p=0.12), energy intake at breakfast (C1: 440 ± 213; C2: 400 ± 158; C3: 440 ± 226; C4: 386 ± 138 calories, p=0.43) or over 24-hours (C1: 16773 ± 532; C2: 1486 ± 434; C3: 1503 ± 321; C4: 1662 ± 505 calories, p=0.28). However, a significant interaction effect was observed in tiredness, calmness, energy and tension (p=0.02). In addition, a significant time (p<0.001) but not condition effect (p>0.05) was observed in TM, ST and state anxiety. Participants’ time to complete cognitive tasks decreased and state anxiety increased over time. CONCLUSIONS: Coffee volume may not have an effect on appetite suppression and perceived hunger, however, may modulate affective responses.