To assess the effects of bisphosphonates (zoledronic acid injection) plus alendronate sodium on bone mineral density (BMD) and levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and insulin-like growth factor I (IGF-I) in patients with osteoporosis. A total of 94 patients recruited from osteoporosis patients hospitalized in the period October 2021 to December 2022 were assigned to either a control group or an observation group using a random number table. The control group was treated with alendronate sodium alone, whereas the observation group received zoledronic acid injection in combination with alendronate sodium administered orally. Pre-treatment values for BMD, serum levels of IL-6, TNF-α, and IGF-I did not differ between the two groups (p > 0.05). However, post-treatment BMD measured at the femoral neck, in lumbar vertebrae, and Ward's triangle were increased, as was serum IGF-I level (p < 0.05). In contrast, in comparison with the control group, reductions were observed in serum IL-6 and TNF-α (p < 0.05). The incidence of adverse reactions such as nausea and vomiting, diarrhea, musculoskeletal pain, and hypocalcemia was significantly lower in the observation group (p < 0.05). Zoledronic acid injection in combination with alendronate sodium increases the expression of IL-6, TNF-α, and IGF-I, suppresses bone resorption and promotes bone recovery in patients with osteoporosis.