This quasi-experimental study explored the impact of inquiry-based instruction on students' conceptions of climate change and their perceptions of science learning environment. A total of 68 senior primary school students participated into the study. Data sources included Questionnaire on Global Climate Change and Constructivist Learning Environment Survey. Data were coded and analysed using quantitative procedures. Before the instruction, about 25% of the participants were aware of the major consequences of, causes of and possible cures for climate change. Following the instruction, about 50-85% of the participants developed scientific understandings about climate change, but the participants showed slow progress in terms of identifying nonscientific conceptions concerning climate change. In addition, students perceived inquiry-based learning environment more encouraging compared to their regular science classes.