Background: Workforce shortage in information technology (IT) has become a pressing issue. To increase the number of female IT professionals, it is important to improve the work environments of female IT professionals. A previous study showed that gender bias is a threat to the outcomes of mathematics tests by females. This influence is called the stereotype threat. Aim: We focused on the stereotype threat to enable female IT developers to deliver their best performance. Method: Using a subjective experiment, we analyzed the relationship between the stereotype threat and the performance of computer programming developers. In addition, we analyzed the effect of eliminating the stereotype threat on programming. Result: Focusing on the time to develop a program, neither the stereotype threat nor the elimination of the threat had any noticeable effect. This result might be affected by the nature of computer programming and a gamification effect.