Image searches are now crucial for obtaining information, constructing knowledge, and building successful educational outcomes. We investigated how reading ability and Internet experience influence keyword-based image search behaviors and performance. We categorized 58 junior-high-school students into four groups of high/low reading ability and frequent/infrequent Internet usage. Participants used Google Image to complete four tasks: finding four images that match four given sentences. The results indicate that reading ability exerted a stronger influence than Internet experience on most search behaviors and performance. Positive relations were found between search performance and two behavior indicators of search outcome evaluation. Students with better reading ability tended to use/revise appropriate keywords, as well as evaluate/select images that matched multiple aspects of the task descriptions. Students with low reading ability/frequent Internet experience tended to enter a single keyword and carelessly select images, while those with low reading ability/infrequent Internet experience tended to use improper keywords and were unskillful in handling search engines. Combined, our results show that successful keyword-based image searches are strongly dependent on reading ability and search result evaluation skills.