To compare the different motivation, intention and behaviour between Chinese and Japanese consumers in naturally dyed fashion consumption we collected 301 Chinese samples and 302 Japanese samples and used a structural equation model (SEM) to analyse the consumption behaviour of naturally dyed apparel based on the planned behaviour theory (TPB) and cross-cultural sustainable consumption framework (CCSC). The results indicate that attitude, social norms and perceived behaviour control (PBC) impact naturally dyed fashion consumption intention and behaviour. Among these relations, intention has a controlling influence on the relationship between subjective factors and actual consumption behaviour. PBC directly affects consumer behaviour. Moreover, the belief system and material source have a significant influence on all TPB constructs, wherein material source has more influence. Comparing China and Japan, attitude has a stronger impact on intention for Chinese than Japanese, but PBC influences Japanese intention more. Theoretically, this paper analyses the factors forming the difference in the strength of the TPB model from a cross-cultural perspective. The differences in Chinese and Japanese consumption behaviours also offer practical insights for the industrial development of natural dyeing.