Photodynamic therapy(PDT) has been recommended as an alternative therapy for various diseases including microbial infection. The aim of the present study is to evaluate the antimicrobial effect of PDT using a photofrin and home made 630 nm Light emitting diode(LED) against Staphylococci. To examine the antimicrobial effect of photofrin-mediated PDT against Staphylococcus aureus and Staphylococcus epidermidis colony forming units(CFU) quantification, and bacterial viability using flow cytometry were formed. The CFU quantification results of S. aureus and S. epidermidis were 1 cfu/ml and 16 cfu/ml of average, respectively, after PDT application with photofrin of $50{mu}g/m{ell}$ and 630 nm LED and energy density of $18J/cm^2$. In addition, S. aureus and S. epidermidis isolates yielded forward-scatter (FSC) and fluorescence intensity (FI) differences on flow cytometry (FCM) after PDT. S. aureus and S. epidermidis cell size(FSC) increased 8.96% and 5.55% respectively, after PDT. Also the numbers of dead cell of S. aureus and S. epidermidis were a 39% and 61% incerased. These results suggest that photofrin-mediated PDT can be an effective alternative treatment for antibacterial therapy.