This study aims to analyze the biology textbook for 10th grades prepared by the Ministry of National Education in Turkey. The present research is based on qualitative research techniques and includes two steps. In the first step, the textbook misconceptions, question types, contents topics, visual materials and measurement and evaluation techniques are investigated. In the second step, the learning approach of the textbook is evaluated by five senior class practicing teachers. The results indicate that the biology textbook contains important misconceptions which can affect learning. As no different types of questions are used, the textbook cannot provide the inquiry according to its questioning techniques. Besides these, it is emphasized by the practicing teachers that the textbook encourages students to memorize and that it should be revised accordingly. In the light of these results practicing teachers need to learn the criteria as to how a textbook must be analyzed and the points to be observed in choosing a textbook.