Background: CdWO₄ is a scintillator with some unique properties. For example, high density, thermal and chemical stability and so on. Different applications of this scintillator such as X-ray scintillator has been investigated thoroughly so far. However, there is limited number of studies reporting the characteristics of CdWO₄ as an alpha counter. Materials and Methods: The CdWO₄ powder was synthesized by a simple co-precipitation method. Then, the CdWO₄ films with different thicknesses were prepared by spin coating method on glass substrates. The CdWO₄ powder and films were characterized by X-ray diffraction, photoluminescence, scanning electron microscopy, Fourier transformed-infrared spectroscopy, and ion beam induced luminescence. Finally, the response of samples with different thicknesses was measured using a ²⁴¹Am alpha source with 1860 Bq activity. Results: The analyses revealed that the nanocrystalline CdWO₄ with about 30 nm size was successfully synthesized without any impurity. Besides, the CdWO₄ films had the same luminescence emission peak characteristics as CdWO₄ powder had. Conclusion: It was observed that the sample with 2.9 mg/cm² thickness had the best counting efficiency (over 2π geometry) among the others.