Knowledge concerning continuously improving branches of science such as biotechnology in particular is difficult to be understood properly by students, or they learn it incorrectly. One of the most important reasons for this is that students cannot associate in their mind the relevant concepts. The aim of this research is to determine prospective biology teachers' conceptual framework of biotechnology, and thus determining their cognitive structure. The data were collected from 34 prospective biology teachers. Considering the fact that these prospective biology teachers had taken biotechnology course previously, they were selected on the basis of volunteering. Word association test and draw-and-write technique were used in collecting the data. The data obtained were organised on the basis of qualitative content analysis. Then the data were grouped into 7 categories (methods/techniques, biotechnology applications, genetics, other branches of science, organisms, meaning attributed to biotechnology, laboratory) according to word association test, and into 4 categories (methods/techniques, biotechnology applications, genetics, organisms) according to draw-and-write technique. According to the research findings, almost half of the prospective teachers had correct and appropriate associations for biotechnology, whereas a considerable part of them did not have adequate conceptual associations. Also, it was found that prospective teachers had misconceptions about biotechnology.