What cannot be found, cannot be used. Consequently, the success of a Website depends, apart from its content, on two main criteria: its top-listing by search engines and its usability. Hence, Website usability and search engine optimization (SEO) are two topics of great relevance. This paper focusses on analysing to what extent selected SEO-criteria, which were experimentally applied to a Website, affect the website’s usability, measured by DIN EN ISO 9241-110 criteria. Our approach followed (i) a theory-based comparison of usability-recommendations and SEO-measures and (ii) a scenario- and questionnaire-based usability evaluation study combined with an eye-tracking analysis. The findings clearly show that Website usability and SEO are closely connected and compatible to a wide extent. The theory-based measures for SEO and Web Usability could be confirmed by the results of the conducted usability evaluation study and a positive correlation between search engine optimization and Website usability could be demonstrated.