The aim of this study was to analyse and compare teachers' attitudes towards inclusive education in two culturally different countries: Finland and Japan. A sample of 362 Finnish and 1518 Japanese teachers participated in this survey. The teachers' attitudes varied and were rather critical. The Finnish teachers were more worried about teachers' efficacy when implementing inclusion, particularly when teaching students with intellectual disabilities or emotional and behavioural problems. The Japanese teachers had a more positive view on the benefits of inclusion for disabled or non-disabled students. Because Finnish schools emphasise the effectiveness of special education, the Finnish teachers in this study were more critical than the Japanese teachers of the idea that the efficacy discourse justifies the need for inclusive education. The findings support the idea that, to improve the universal understanding of inclusive education, more research should be done to analyse how inclusive education developments are realised in different cultural and historical contexts.