A virtual classroom constructed with virtual reality technology enables a more intuitive and immersive experience for learners. The classroom climate is an important factor affecting students' learning experience and performance in a virtual environment. However, there is a lack of research on the role of climate on learning experience and performance in virtual classrooms. This study investigated the effect of classroom climates (positive, neutral, and negative) on students' learning experience (cognitive load, learning motivation, and emotion) and performance (behavior and outcome) in a virtual environment. A total of 96 undergraduate students participated in the study. The results indicated that learners performed better when they perceived a positive classroom climate. Compared with the neutral climate group, the negative climate group reported stronger immersion, more active behavior, and better learning outcomes. The findings provide evidence for instructors and designers to create a suitable climate to improve students' learning experience and performance in a virtual environment.