This paper describes a 14-year-old male patient who complained of memory problems during treatment with fluoxetine for major depression. The patient showed impairments on all five scales of the Wechsler Memory Scale-Revised during fluoxetine treatment. Three of the scales, Verbal Memory, Visual Memory, and General Memory, showed statistically significant improvements after fluoxetine was discontinued. This case represents the first time memory deficits related to fluoxetine were quantitated with a standardized memory test. It points to cognitive side effects that need to be understood.