Content analysis of the studies of both Turkish and foreign authors on PBL in science education in national and international journals was made considering such variables as the research subject, method, sample, diversity of data collection tools and the data analysis methods. To this end, content analysis of 104 papers - 42 by Turkish authors and 62 by foreign authors - which were carried out between the years 1986-2012, was made. All these papers were accessed in full text. It was identified that in 40.4% of the studies whose content analysis was made, the focus was on the effect of PBL on learning, while in 35.6% the focus was on concept analysis. It is seen that while Turkish authors worked on teaching studies in 59.5% of their studies, foreign authors focused on concept analysis in 41.9% of their studies. Also while Turkish authors mostly preferred quantitative research methods (61.9%) in their studies, foreign authors preferred qualitative research methods (66.1%). The commonly used data collection tools for Turkish authors were questionnaire and achievement test, while foreign authors preferred interview and alternative data collection tools. In terms of choosing a sample group, it is seen that studies with undergraduate and secondary school students (9-12) were referred more often. The findings of the study reveal that studies on PBL were not very common in our country until 2005; that they reached the highest number between the years 2005-2009, and that foreign authors published the highest number of papers in 2006. While the foreign authors had a superiority over Turkish authors in terms of their papers on PBL in science education until 2005, it is seen that as of 2005, except the year 2006, the number of papers of Turkish authors has been equal to/higher than the number of papers by foreign authors until 2012. Besides, it is also identified that most of these studies were mixed and in the field of chemistry education. It is believed that this study is significant in terms of providing an opinion to young researchers working in the field of PBL and to those who are planning to work in the field.