BACKGROUND: Gender differences in the prevalence and characteristics of misuse of methamphetamine (meth) and prescription stimulants were examined in a representative US sample of youths and young adults aged 16-25 (N=24,409). METHODS: Stimulant misusers were categorized into three mutually exclusive subgroups: meth users only, meth and prescription stimulant users, and prescription stimulant users only (e.g., Benzedrine, Ritalin, or Dexedrine). Multinominal logistic regression analyses identified the characteristics associated with misuse of meth and prescription stimulants. RESULTS: About 1 in 10 youths reported any misuse of stimulants in their lifetime. Prescription stimulant misuse occurred earlier and was more frequent than meth misuse. About 47% of meth misusers also reported prescription stimulant misuse. Among misusers of meth and prescription stimulants, males were more likely than females to misuse methylphenidate (82% versus 65%) but were less likely to misuse diet pills or amphetamines (37% versus 49%). Multinominal logistic regression analyses indicated that all subgroups of lifetime stimulant misuse were associated with past year substance abuse. The characteristics of meth misusers differed slightly from prescription stimulants misusers. CONCLUSIONS: Multidrug use is common among stimulant misusers. Parents should be informed about the risk of prescription stimulant misuse by their youths.