Aim. To study the efficacy of Zoledronic acid in the treatment of benign osteolytic tumours or tumour like conditions of bone as a therapeutic or as an adjuvant agent. Method. 31 patients- 19 female, 12 male, age from 8 yrs to 42 yrs, were treated with intravenous zoledronic acid. In 17 patients (fibrous dysplasia-10, nonossifying fibroma- 4, UBC- 3) zoledronic acid alone was used as a therapeutic agent. In 14 patients (ABC- 3, GCT- 11), it was used as an adjuvant agent after curettage. Four patients presented with pathological fracture. In all patients, 4 mg. zoledronic acid was given at 2 monthly intervals. In 12 adult patients, in addition oral bisphosphonates - alendronate was given weekly for at least 6 months. Results. Patients were evaluated using visual analog pain scale and x-rays. At last follow-up (6-40 months), in 15 patients, treated with zoledronic acid alone, there was thickening of cortices and reduction in the size of the lesion. Pain score decreased from an average of 8 to 2. All four fractures healed. In 2 patients, there was progression in size of the lesion. In 14 patients, where it was used as an adjuvant agent, there was early thickening of bone cortices. There was no local recurrence in this group. There was no adverse reaction to the drug in any of the patient. Conclusion. Zoledronic acid is a third generation bisphosphonates and a proven anti-osteolytic agent. It has proved effective in the treatment of number of osteolytic conditions. Our study also suggests that Zoledronic acid not only help to stabilize these lesions but also resulted in pronounced healing in majority of the patients. It also reduced recurrence rate in aggressive benign bone tumours such as ABC or GCT when used as an adjuvant treatment