The general purpose of this research is to introduce the effect of locus of control in web based problem based learning (PBL) on students' attitudes to the web based and problem based learning. In this study, one of the real experimental types, which is prolix experimental pattern with mono factor and three groups, was used. This study was performed on totally 72 students freshmen of four different programs of Gazi University Vocational School of Health Services. The students, who were divided according to the locus of control, were studied in groups of eight. A web presented learning material about first aid lecture was developed for performing the effects of problem based learning (PBL) on students. Five scenario of problem, for to be used during the time of analysis, were formed to make students scope out. Totally a 12 week analysis was performed. Statistical analysis were performed by SPSS 11.5 package program and 0.05 significance level was taken as a basis in all statistical analysis. It was obtained that internal controlled students showed more constructive attitude to web based learning then the external controlled students and students with indeterminable locus of control. It was obtained that internal controlled students and students with indeterminable locus of control showed more constructive attitude to problem based learning then the external controlled students.