Background: Most students have exhibited low motivation to engage in traditional learning methods. Additionally, students have difficulty concentrating on the course content, being easily distracted by their smartphones. Objectives: Therefore, we adopted an online 3D gamification problem-based learning (PBL) model to motivate students and improve their learning satisfaction and achievement on a human resource development course. Methods: We followed the ADDIE instructional design model and used four essential topics to formulate our teaching activities in the three-dimensional sandbox game, Creativerse. Moreover, this paper conducted an explorative study by using ANCOVA and partial least squares structural equation modelling to test student learning achievement and analyse the relationships between components such as performance expectancy (PE), effort expectancy (EE), social influence (SI), and facilitating conditions (FC). Results and conclusions: Our online 3D gamification PBL model enhanced learning achievement on the courses; moreover, FC is the most critical factor influencing learning satisfaction. This study provided suggestions for operating an online 3D gamification PBL teaching approach. Implications: The current paper also explained how students' learning satisfaction relates to these significant factors. Moreover, this study's findings will help instructional designers and instructors to develop online 3D gamification learning environments.