Zinc oxide nanoparticles (ZnO) were synthesized using aqueous leaf extract of Pinus roxburghii L. (Chir) via green synthesis as due to least toxic effect on environment, green synthesis has become one of the most important methods for the synthesis of particles at nanoscale. Ultraviolet- Visible (UV-Vis) spectrum was used to assess the size of synthesized nanoparticles, XRD and SEM analysis was further used to confirm the exact size and shape of these green nanoparticles, while functional groups were recorded by using FTIR analysis. Change in color of the reaction mixture (pale yellow to whitish) was the visual confirmation of ZnO particles while UV- Vis analysis presented a sharp peak at 377 nm which confirmed that the synthesized particles were in nanoscale range. Hexagonal wurtzite structure of ZnO nanoparticles was confirmed through XRD analysis which gives distinct peaks at 2θ position. The average size of nanoparticles was around 24.71 nm with irregular shape of particles. Leaf extract of P. roxburghii L. was found excellent reducing agent for the synthesis zinc oxide nanoparticles.