The purpose of the study is to investigate the level of understanding the science process skills of pre-service teachers studying in the primary school teaching program and the predictions of the lecturers about the pre-service teachers' answers. The descriptive model was used as it was aimed to present a case in the study. The first study group of the study consists of 68 pre-service teachers studying in the third year of the primary school teaching undergraduate program of a state university, and the second study group consists of 5 instructors working at the same faculty and conducting courses on science. As a data collection tool, the opinion form consisting of twelve open-ended questions prepared by the researchers and the grouped answers of the pre-service teachers were used. Descriptive analysis method was used to analyze the collected data. The answers written on the opinion form based on the skills of observation, classification, measurement, collecting data, recording data, designing and conducting experiments and interpreting data were examined. Almost all of the pre-service teachers wrote relative answers to the questions asked. It was determined that the predictions made by the instructors about the answers written by the pre-service teachers were proportionally different. In the study, although the level of understanding of the pre-service teachers' scientific process skills was considered sufficient, it was concluded that there were significant deviations between the predictions of the instructors and the percentages of the answers written by the teacher candidates.