Objective: To analyze the influence of oblique-pulling manipulation on the stress and displacement of sacroiliac joint (SIJ) and iliolumbar ligament by finite element analysis; and to explore the mechanism of oblique-pulling manipulation in treating sacroiliac joint subluxation. Methods: The finite element lumbar spine-pelvis model was established. The iliolumbar ligament and articular cartilage were reconstructed according to the real tissue structure of human body. Compression, tensile and oblique-pulling tests were performed in order to analyze the stress and displacement of sacroiliac joint and iliolumbar ligament after model validation. Results: When the oblique-pulling manipulation load, the stress(35.174MPa), displacement(0.553mm) and Range of Motion( 0.62°) of SIJ were maximized. And the total stress(4.717MPa) and displacement(1.6042mm) of iliolumbar ligament also happen by oblique-pulling manipulation. Conclusions: The effect of oblique-pulling manipulation on the SIJ and iliolumbar ligament is most obviously in these three modes. We suppose that it can cause slight separation and rotation of SIJ and change the stress distribution, but the tensile effect on iliolumbar ligament is more obvious.