Polycaprolactone (PCL) to which has been added zinc oxide nanoparticles (ZnO NPs) produces nanocomposites (PCL/ZnO NCs). These nanocomposites can be used in biomedical applications and in the food packaging sector. However, for these materials to be used in these applications, they need to be sterilized. For this, gamma irradiation is the most common method. Thus it is important to evaluate the effects of gamma irradiation on the properties of PCL and PCL/ZnO that have been exposed to gamma irradiation. PCL/ZnO NCs films were obtained by solvent casting and exposed to gamma irradiation at 25 kGy and evaluated by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) scanning electron microscopy (SEM) and mechanical properties. Mechanical properties and crystallinity showed marginal variations for the irradiated samples. The results obtained demonstrate that gamma irradiation at 25 kGy, did not cause profound changes in nanocomposite properties.