Objective To investigate the proximal femoral nail anti-rotation (PFNA) for treatment of type 31-A2 intertrochanteric fractures patients with osteoporosis by two postural approaches. Methods A total of 92 patients with type 31-A2 intertrochanteric fracture and osteoporosis admitted to the Fouth Department of Orthopedics and Traumatology, Lu′an Hospital of Traditional Chinese Medicine from December 2014 to May 2019 were selected for study, and they were divided into the experimental group and the control group according to the random number table method, with 46 patients in each group. In the experimental group, PFNA was placed in the healthy lateral position, while in the control group, PFNA was placed in the supine position. The two groups were compared for general information, surgical conditions, incidence of recent complications, length of hospital stay, hip function, and long-term follow-up. Results There was no significant difference in operation time between the two groups (P > 0.05). The experimental group had less intraoperative blood loss, postoperative drainage volume and total incidence of recent complications, and shorter the length of hospital stay than the control group, with statistically significant differences (all P < 0.05). During follow-up, three of the 46 cases in the experimental group fell off, leaving 43 cases, and four of the 46 cases in the control group fell off, leaving 42 cases. Harris function score was higher in the two groups at each time point after surgery than before surgery, and the differences were statistically significant (all P < 0.05). There was no significant difference in Harris function scores between the two groups before and 12 months after surgery (P > 0.05). Harris function scores one and six months after surgery in the experimental group were higher than those in the control group, with statistically significant differences (all P < 0.05). The weight bearing time and fracture healing time of the experimental group were shorter than those of the control group, and the incidence of fractures around internal fixation was lower than that of the control group, with statistically significant differences (all P < 0.05). There was no significant difference in the incidence of surgical failure and secondary surgery between the two groups (P > 0.05). Conclusion PFNA placement in lateral lying uninjured position for treatment of type 31-A2 intertrochanteric fracture with osteoporosis can reduce the length of hospital stay and the incidence of recent complications, restore hip function earlier, and shorten the time of underground loading and fracture healing.