The purpose of this study is to evaluate the effectiveness of the co-benefits of reducing air pollutant emissions for renewable power generation Clean Development Mechanisms (CDMs). We also quantitatively discuss how co-benefit values depend on the emission standard policies. For this purpose, long-term baselines are developed considering the emission reduction policies and renewable energy promotion measures in China and India. And a new assessment of marginal damage cost of air pollutant emissions is performed based on a social survey conducted in several Asian cities. Due to the emission standard promulgated in 2011, the baseline emissions of air pollutants on a long-term are significantly decreased in China. The co-benefits of reducing air pollutant emissions per avoided carbon dioxide (CO2) emission is shown to be much lower than the values reported in previous studies, and the positive effect of the co-benefits of CDMs is rather limited. For the Indian baseline, where an air pollutant emission standard is assumed only for particulate matters, the co-benefit values of reduced air pollutant emissions are found to be close to those reported in previous studies, and the inclusion of co-benefits for CDM evaluation is found effective in improving the viability of renewable power generation CDMs. (C) 2015 Elsevier Ltd. All rights reserved.