The primary goal of this study was to examine whether electronic diaries are a feasible method of monitoring transitory emotional states with a school-age, community sample of youth. A second goal was to examine preliminary relations between indices of emotional functioning captured via electronic diaries and other measures of child emotional and psychological functioning. Participants included 38 youth between the ages of 7 and 12 (51% males, M age = 9 [1.52] years and 49% females, M age = 9 [1.94] years) and their mothers (M age = 39 years) and fathers (M age = 42 years). Children were prompted to indicate the intensity of their current emotion four times a day for 1 week using Palm Tungsten E2s. Youth also completed self-report measures of emotion intensity, awareness, and dysregulation. Parents completed measures of child emotion regulation and symptoms of externalizing and internalizing psychopathology. Sixty percent of the prompts were answered as intended. Higher levels of positive emotion intensity based on electronic diary ratings were negatively related to parent reports of adaptive emotion regulation and were positively related to youths’ reports of emotion dysregulation and poor emotion awareness. Given that the electronic diary data offered unique information on youth emotional functioning, strategies to increase compliance with the diaries are suggested.