The question style in high school environmental science textbook was examined in terms of the placement, frequency, and type of question, and then analyzed the kind of scientific inquiry process elicited by the question in the topic of textbook using the Textbook Questioning Strategy Assessment Instrument (TQSAI). The average number of question per topic was only 0.6. The number of all question in the high school environmental science textbook was very little ; the number of non-experiential question was 8 and that of experiential one was 3. The total number of sentence was 1,236 and the ratio of the number of question to that of sentence was 0.9%. The frequency of non-experiential question was higher than that of experiential one. In action part of the textbook, there were more kinds of question styles than in the main part.