<p>This study develops and evaluates the antibacterial sportswear using silver-plated threads with antibacterial and deodorizing properties. A silver-plated thread was applied to the axillary area, and a well-fitted antibacterial sportswear pattern was produced. To verify the effectiveness of the developed antibacterial shirt, the developed shirt was worn alternately with a T-shirt made of commercially available antibacterial fabric. After 30&#xa0;min of exercise, the bacterial count was measured using the adenosine triphosphate luminescence-measurement method, and the change in bacterial count after 3&#xa0;h was analyzed. In addition, changes in temperature and humidity inside the clothing, and subjective wearing comfort were evaluated. The results showed that the developed antibacterial T-shirt had a lower bacterial count in the axillary area than the T-shirt made of commercially available antibacterial fabric, and the amount of bacteria was significantly reduced after 30&#xa0;min. No difference in the temperature inside the clothing was observed between the two T-shirt types; however, when exercising for 30&#xa0;min wearing each of the two shirts, the change in humidity inside the developed T-shirt was very little compared to that in the T-shirt made of commercially available antibacterial fabric. In addition, the developed T-shirt was evaluated as excellent in a subjective evaluation.</p>