Objective To investigate the relationship between the occurrence of postoperative complications and anemia in the elderly with hip fracture, and to further determine whether anemia is a risk factor for predicting the complications after hip fracture. Methods A total of 744 hip fracture patients aged over 50 years undergoing hip fracture surgery in our hospital over the period of October 1, 2009 to October 1, 2011 were enrolled in this study from the hip fracture data of the Chinese PLA General Hospital. Their clinical data were collected and retrospectively studied. The cohort was divided into anemia and non-anemia groups based on the hemoglobin level on admission. Multivariate logistic regression analysis was applied to assess the association between anemia and the complications. Results The age was older, and the constituent ratios of patients receiving blood transfusion, having intertrochanteric fracture and undergoing intramedullary fixation treatment were significantly higher in the anemia group than in the non-anemia group (P＜0.05). There were more patients having fever, postoperative complications and respiratory complications in the former than in the latter groups (P＜0.05). After adjustment for age, sex, American Society of Anesthesiologists (ASA) physical status classification score and other risk factors, logistic regression analysis showed that anemia increased the risk for postoperative fever and pulmonary complications (P＜0.05), and it also significantly increased the incidence of postoperative overall complications in female patients (P＜0.05) . Conclusion Anemia is an independent risk factor for pulmonary complications and postoperative fever after hip fracture in the elderly. And for the female elderly, it is also an independent risk factor for overall complications.