This research is stimulated by the study of PISA which is showed that the critical thinking in Indonesia each year can be considered relatively low, it is in line with the observation of researchers in the field that showed students in Indonesia, especially in Sub Kutawaringin average not ready to accept the critical thinking matters. Therefore, it needs an effort to increase the critical thinking, by using the learning model brainstorming. This research aims to know the effect of brainstorming model on the elementary schools 5th grade students' critical thinking at Kutawaringin, Bandung, and get the picture of the students' critical thinking ability difference between students using brainstorming against students using conventional learning method. The method used in the research is experimental quasi with research design used is Quasi Experimental Deisgn which is Nonequivalent Control Group Design. Then the grade of critical thinking ability collected is analyzed and interperted which indicated (1) the grade of students taught with brainstorming model is better than students' grade taught with conventional learning method; (2) students' critical thinking ability grade shows relatively high improvement when using brainstorming learning method. Based on this explanation, the brainstorming learning model can be used by teachers as one of the alternative to improve the students' critical thinking ability.