The purpose of this study was to establish a simple laboratory model for reproducing dental unit waterlines (DUWLs) biofilms. The bacteria obtained from DUWLs were cultured into an R2A liquid medium for 10 days, following which the culture was stored at -70℃. This stock was then inoculated into the R2A liquid medium and incubated in batch mode. After culture for 5 days, it was inoculated into biofilm formation models containing polyurethane tubing pieces and R2A liquid medium. The biofilm formation was carried out in a well plate model, a CDC biofilm reactor model, and our simple laboratory model. After the biofilm formed for four days in each model, biofilm accumulation, thickness, morphological characteristics and distribution of the composing bacteria were compared. Biofilm accumulation was significantly higher in the well plate model. Biofilm accumulation in the simple laboratory model and the CDC biofilm reactor model was similar. The biofilm within polyurethane tubing was distributed widely and thinly in the well plate model. In the simple laboratory model and the CDC biofilm reactor model, thick bacterial lumps were observed in some parts. Therefore, the simple laboratory model was selected as the final model for testing DUWL disinfection. The effectiveness of disinfectants such as sodium hypochlorite, hydrogen peroxide and chlorhexidine was tested by application to the biofilm formed in the simple laboratory model. Because the lower concentrations of disinfectants were less effective in the reducing the count of bacteria constituting the biofilm of the simple laboratory model is appropriate for comparison of disinfectant effects. This model is expected to be used for experiments for various purposes in further studies.