Consumers’ interests in the environment have been growing; hence, their consciousness about the environment has changed and affected their clothing shopping behavior. Prior study indicated attitude-behavior inconsistency in eco-friendly consumer behavior. It was because consumers’ consciousness or attitude was often measured at an abstract level, not at a product specific level. This study investigated eco-friendly clothing knowledge, eco-friendly clothing consciousness, and ecological clothing consumption behavior. The effects of consumers’ level of clothing involvement and subjective norms in this process were also investigated. For the empirical research, a questionnaire was developed, and responses from 480 women in their 20s to 50s were statistically analyzed. Results indicated that interest and fashion consciousness dimensions of clothing involvement had a significant influence on ecofriendly clothing knowledge, which thereby significantly influenced the three factors of eco-friendly clothing consciousness: social responsibility, health orientation, and clothing resource-saving consciousness. Such factors had different roles in the clothing consumption process. Social responsibility had a significant influence on the entire process of clothing consumption: shopping, purchasing, using, and disposing behaviors. Health orientation consciousness had a significant influence on shopping and purchasing behaviors, whereas resource-saving consciousness had a significant impact only on shopping behavior. Subjective norms were significantly correlated with all aspects of the clothing consumption process. Influence on disposing behavior was relatively weaker than other aspects of clothing consumption behavior.