This study aimed at exploring the effect of Fermi question on the development of science process skills in the physics subject at ninth Grade students. The sample of the study consisted of (2) classes for males and (2) classes for females, which were randomly divided into (2) groups: An experimental group of (41) students divided into a class of (21) males and a class of (20) females. This group was taught through the Fermi question. A control group of (44) students divided into a class of (23) males and a class of (21) females. This group was taught through the traditional method. Science process skills test was prepared by the researchers according to the purpose of the study. The test was administered before and after the treatment. The results of the study showed that there were statistically significant differences (a = 0.05) in science process skills test (in favor of experimental group), and that there were statistically significant differences (a = 0.05) due to gender in favor of females.