The article focuses on the issue of visuals in geography textbooks and their assessment. The issue is explained from the perspective of educational and cognitive psychological theory and the theory of textbooks. The general purpose of the presented research is to develop a research instrument for categorising the types of visuals in geography textbooks and for assessing their instructional qualities--their abstractness, text relatedness and caption aptness. The investigation was conducted as a content analysis of 963 visuals in five Czech lower secondary human geography textbooks. The research findings showed that in the analyzed textbooks realistic visuals predominate, photographs in particular. Evaluation of relation between the visuals and expository text proved a more or less equal representation of text related visuals and text elaborating visuals. As far as the caption aptness of visuals in geography textbooks is concerned, the most commonly represented ones are identifying captions and extensional captions. The research documented that recommendations of educational and psychological research are not sufficiently reflected in the analysed textbooks which provides opportunities for applied research into this area as well as for textbook production.