This study explored the effect of ChatGPT on the speaking self-efficacy level of English as foreign language learners. The research followed the mixed method approach and involved a total of 65 participants who were randomly assigned to the experimental and control groups. The experimental group used the ChatGPT for communicative activities, while the control group was engaged in a regular EFL classroom. The data collection procedure included the administration of the EFL speaking selfefficacy scale and an interview with the experimental group as optional participation. The t-test on independent samples showed non-statistically significant differences in speaking self-efficacy levels of the two groups before the intervention. Nevertheless, the covariance (ANCOVA) analysis after ten intervention sessions revealed noteworthy enhancements in speaking self-efficacy among learners in the experimental group. The interviews revealed that engaging with ChatGPT facilitated learners in developing confidence in their conversational skills, managing their stress levels, and deriving pleasure from the learning experience. The results indicated that interactions facilitated by AI chatbots, like ChatGPT, fostered a conducive learning environment for learners, leading to increased confidence in speaking.