In recent years, green (sustainability) issues have been more and more mentioned by the media, businesses, industries, politicians, financial institutions, consumers and the general public. There has been much discussion about the damaging effects of daily activities on the environment. Endless consumption, manufacturing and marketing are the main responsible agents for the environmental damage. Green companies have been trying to decrease their damaging effects through different green practices to protect both the environment and their corporate reputation. Green practices have critical importance for the world's sustainability while the corporate reputation is a vital value for sustainability of the companies. Building strong corporate reputation is fairly difficult for the companies in today's competitive market environment. This study aims to examine the effect of companies' green practices on corporate reputation in the banking sector and the moderator effect of customer attitudes towards green practices on this relationship. To understand green practices-corporate reputation relationship, the 480 private customers of four (two green and two non-green) Turkish banks were interviewed and 451 valid questionnaire were obtained. The banking sector was chosen to understand customer reactions in the absence of considerable individual benefit through green practices. The findings show that green practices have significant effect on corporate reputation and costumer attitudes towards green practices have significant moderation effect on the relationship between green practices and corporate reputation.