The aim of this study is to develop an electronic portfolio attitude scale (EPAS) for prospective teachers. The scale, which was prepared during the scale development phase, was applied to 524 prospective teachers studying in the third and fourth grade. Exploratory factor analysis results (EFA) showed that 40 items in the scale were gathered under three factors. These are: "benefit for the student", "denial (negation)" and "effectiveness in terms of the instructional process". The three-factor structure obtained by confirmatory factor analysis was confirmed. When these factors are evaluated together, their contribution value to the total variance is 39.37%. Factor loadings were found to vary between .33 and .71. However, according to the results obtained in the item analysis, it was determined that all the items in the scale were distinctive. In addition, it is seen that the CR value is greater than .70, and the dimensions of the scale fulfill the composite reliability requirement. In addition, as a result of ANOVA, it was revealed that the attitudes of prospective teachers towards e-portfolio differ significantly according to their knowledge about e-portfolio and their competence in using technology. The McDonald’s ω coefficient (known as congeneric reliability) of the three factors in the scale were .97, .91 and .88, respectively, and the McDonald’s ω coefficient for all items of the scale was .96. As a result of the reliability and validity analysis, it was concluded that the electronic portfolio attitude scale is a reliable and valid measurement tool for prospective teachers.