Self-reported feelings of anxiety after separate administrations of ethanol (0.75 mL/kg), low-dose diazepam (0.12 mg/kg), high-dose diazepam (0.20 mg/kg), and placebo were evaluated over four laboratory sessions in the same 90 male volunteers, who used the Spielberger State Anxiety Inventory (STAI). Significant increases in the state anxiety scores were observed after administrations of diazepam and ethanol, while a significant decrease in the feelings of tension was reported after administration of placebo. Consistent with previous work from our laboratory, there were similarities in the intensity and time course of change observed for a number of measures following low-dose diazepam and ethanol infusions. The potential importance of these findings to the understanding of intoxication and abuse of benzodiazepines is discussed.