Although experimentally induced positive mood can generally last for 20 min and the induced mood is conducive to creative performance, it is still unclear whether the facilitation effect is stable during these 20 min. Two studies were conducted to examine this issue while controlling for the impacts of task switching, practice effect, and test item differences. In Study 1, participants (N = 42) were randomly assigned to positive, negative, and neutral mood conditions. After watching a short video clip, participants answered four items of the Alternate Uses Test (AUT) in 20 min, with 5 min allotted for each item. Creative performance during each 5‐min period was scored in terms of fluency and flexibility. Separate repeated‐measures analyses of variances on these creativity scores showed that positive mood consistently enhanced performance over 20 min. Study 2 further eliminated the effects of test item differences and test order. Participants (N = 131) underwent the same mood induction procedure and answered the same four items of the AUT, except that these items were presented in four different sequences in accordance with the Latin square design. Consistent with the findings in Study 1, Study 2 showed that the facilitation effect of positive mood lasted for 20 min when the interference of task switching, practice effect, and test item differences were minimized. This finding not only sheds light on the debate regarding the stability of experimentally induced positive mood effect, but also contributes to the body of empirical evidence that future studies may use to examine the positive mood effect over a relatively long period of time.