Background: Although it is rare for the fracture itself to become a life threatening injury in patients suffering from rib fracture, the lives of these patients are occasionally threatened by other associated injuries. Especially, early discovery of patients with rib fracture and intra-abdominal organ injury is extremely important to the prognosis. This study analyzed the link between rib fracture and intra-abdominal injury to achieve improved treatment. Materials and Methods: Among trauma patients that had visited the hospital emergency room from January 2007 to December 2009, a retrospective study was conducted on 453 patients suffering from rib fracture due to blunt trauma. Rib fracture was classified according to location (left, right, and bilateral), and according to level (upper rib fracture [1-2nd rib], middle rib fracture [3-8th rib], and lower rib fracture [9-12th rib]). The researched data was statistically compared and analyzed to investigate the correlation between the location, level, and number of rib fracture and intra-abdominal organ injury. Results: Motor vehicle injury was found to be the most common mechanism of injury with 208 cases (46%). Associated injuries accompanied with rib fracture were generated in 276 cases (61%). Intra-abdominal organ injury was discovered in 97 cases (21%). Liver injury was the most common intra-abdominal injury associated with rib fracture with 39 cases (40%), followed by spleen injury, with 23 cases (23%). Intra-abdominal injury according to level of rib fracture was presented as upper rib fracture in 11 cases (11%), middle rib fracture in 31 cases (32%), and lower rib fracture in 55 cases (57%), thus verifying that intra-abdominal injuries were commonly accompanied in lower rib fractures (p=0.03). In particular, significant increase of intra-abdominal injury was presented in fractures below the 8th rib (p=0.03). The number of intra-abdominal injuries requiring emergency operations was significantly higher in patients with more than 6 rib fractures (p=0.04). Conclusion: Intra-abdominal organ injury is more common in patients with lower rib fracture, especially fractures below the 8th rib. Intra-abdominal organ injuries generated in multiple rib fracture patients with more than 6 fractures significantly higher severity. These cases must be thoroughly inspected and carefully observed as there is possibility of emergency operation.