Using living organisms in biology education is a common practice that provides students with direct contact with living beings in the classroom. Several benefits and barriers of using organisms in classrooms have been proposed in the literature. Hence, biology teachers should carefully consider the pros and cons of using living organisms, and decide whether the use of living organisms for the learning goal at hand is appropriate. This mainly quantitative study focused on biology teachers' views towards the following questions: (1) to what extent do biology teachers use specific kinds of organisms in their classrooms? (2) to what extent do biology teachers encounter administrative issues, which are potentially complicating the use of living organisms at their schools? (3) to what extent do biology teachers view specific benefits and barriers of using living organisms in their classrooms? A sample of 86 in-service biology teachers answered a questionnaire that was developed specifically for this study. The study provides some relevant findings for biology education. For example, plants seem to be used relatively often in classrooms, the teachers rated the benefits of working with living organisms significantly higher than the barriers, and supportive conditions at schools might enhance the use of organisms in classrooms.