Objective:To study the pharmacokinetic interaction after oral administration of atomoxetine and fluoxetine in rats.Methods: After oral administration of atomoxetine and fluoxetine, drug levels in plasma were measured by HPLC. The plasma concentration-time data were accessed by 3p97 and the pharmacokinetic parameters were obtained. The interaction of the pharmacokinetics between atomoxetine and fluoxetine were valuated by student-t test. Results: When atomoxetine was co-administered with fluoxetine, the t1/2, Cmax,AUC of atomoxetine has been significantly increased, and the pharmacokinetic parameters of fluoxetine had little variance. Conclusion: There was obvious interaction of pharmacokinetics when atomoxetine and fluoxetine were co-administered, and the concentration of the atomoxetine plasma should be monitored when they were used in combination.