Onshore wind farms have the advantage of a lower cost than offshore wind farms, but their negative environmental impact has been pointed out as a problem. If this environmental impact can be lessened, public acceptance of onshore wind farms will be significantly increased. This study investigates public attitudes to the lessening of the environmental impact of onshore wind farms, focusing on three specific attributes: visual impact, ecosystem destruction and noise pollution. The area of empirical analysis is South Korea, and the choice experiment data are analysed using a mixed logit model to reflect the heterogeneity of the respondents’ preferences. The analysis results show that there is considerable heterogeneity in respondents’ preferences and that they regard the visual impact and the ecosystem destruction as more important than the noise pollution. Respondents are willing to pay KRW 197, KRW 138 and KRW 69 for a 1% improvement in visual impact, a 1% reduction in ecosystem destruction and a 1-dB reduction in noise, respectively. The results of the scenario analysis show that simultaneous improvements in the three attributes should be made in order to ensure a certain level of public acceptance. Related policy implications are provided based on the analysis results.