Cognitive field is an area where mental learning related to mental abilities arising from information and information is concentrated, mental abilities are developed and mental activities are tried to be revealed and it also serves to design teaching. The aim of this study is to evaluation of the questions forming according to the Bloom's taxonomy by pre-service mathematics and science teachers. The participants of the study are a total of 67 pre-service teachers, 37 of whom were from the elementary mathematics teaching program and 30 from science teaching program. As a part of the measurement and assessment course, pre-service teachers were asked to forming a question to each of the cognitive process dimension of Bloom's taxonomy. The data were analyzed by three experts comparing the questions with respect to the levels. At the end of the study, it was determined that pre-service teachers had difficulty in distinguishing levels of the cognitive domain from each other while preparing the questions. In addition, pre-service teachers had difficulty in forming questions that were appropriate especially with respect to the upper level steps in the most analysis level. On the basis of the branches, it was seen that pre-service science teachers generally were higher rate of correct question writing with respect to the steps than the pre-service mathematics teachers. It has been seen that mostly the pre-service teachers confused the application step with the most comprehension and the synthesis steps, the analysis step with the most comprehension and the application steps, the synthesis and the evaluation steps with the most the analysis step. In future studies, it is suggested that studies should be conducted to determine the causes of these difficulties experienced by pre-service teachers and to eliminate their deficiencies.