Objective To investigate the effects of total hip replacement (THR) and dynamic hip screw (DHS) to intertrochanteric fracture in the geriatric with serious osteoporosis. Methods The clinical data of 51 senile cases (age over 60 years) with serious osteoporosis (Singh index less than grade Ⅲ ) cured from January 2003 to March 2008 were retrospectively reviewed. Two different groups were randomly selected from all cases treated with THR and DHS. Nineteen cases of THR were selected in THR group, modified Gibson approach was taken to complete hip joint replacement Thirty-two cases of DHS were selected in DHS group,lateral hip approach was employed to complete DHS fixation. Mobilization by CPM from the 2nd day and weight burdening from 3rd to 7th day according to general physical condition after surgery were carried out in THR group, mobilization and weight bearing start according to different conditions from the 2nd to 10th week in DHS group. Results Among 51 cases, 47 cases had got follow-up for 5.0 -40.5 (28.1 ± 11.9) months. Nineteen cases in THR group had got follow-up, Harris hip score of 18 cases (94.7% ) were good or excellent, and the other 1 case was bad. Twenty-eight cases in DHS group had got follow-up. Harris hip score of 23 cases (82.1% ) were good or excellent, and the other 5 cases were bad. There was statistical significance between the two groups (P < 0.05 ) . The average periods to start partly weight bearing of THR group and DHS group were( 8.3 ±4.2) days and (43.6 ± 15.3) days respectively, there was statistical significance between the two groups (P< 0.05). Conclusion To the geriatric intertrochanteric fracture with serious osteoporosis, THR is a better choice than DHS, because THR has shorter recovery period before full weight bearing, higher hip functional outcome evaluated by Harris hip score, earlier recovery of mobilization and less complications related with long term bed-bound .