The intent of this explanatory sequential mixed-method study is to examine Islamic teachers' thoughts on improving critical thinking skills in elementary schools in the Southwestern province of Saudi Arabia. This study involves the collection of quantitative data and an explanation of the quantitative results with qualitative data. In the first phase, a survey was administered to Islamic teachers in Saudi elementary schools to assess their opinions on improving students' critical thinking skills and to identify the factors that influence or hinder their implementation of critical thinking instruction. In the second phase, qualitative data was collected using semi-structured interviews with a number of Islamic teachers in order to explore more fully their perceptions toward improving students' critical thinking skills in Saudi elementary schools. In regard to the barriers for improving the critical thinking ability of elementary education students, the participants reported seven major obstacles, which are student ability, teaching methods, classroom structure, Saudi society and the school community, pre-service teachers preparation programs and in-service teacher professional developmental programs, and the Islamic studies curriculum. The highest ranked obstacle to improving critical thinking for elementary education students was student ability, with an overall mean of 4.31 on a 5-point scale while the Islamic studies curriculum was the lowest ranked obstacle with a total mean of 2.57. This study highlighted there is a need to examine female Islamic teachers' perceptions toward critical thinking in the Southwestern region of Saudi Arabia in order to identify the similarities and differences between the perceptions of male and female teachers.