Introduction: Colour stability of the material is an essential factor that contributes to the selection of a flexible den- ture material. Staining effects on the denture may result in unattractive appearance, the dissatisfaction of the wearer, and limited usage period of the denture. This study aims to identify the colour stability of the Valplast flexible denture material using three types of beverages. Methods: A total of 32 disc-shaped flexible resin materials (20 +/- 0.1 mm in diameter and thickness 3 +/- 0.1 mm) were prepared based on the manufacturer instructions. The samples were randomly divided into 4 groups of immersion: distilled water (control), coffee solution, tea solution and red wine. The samples were left in the specified immersion solution for up to 60 days. Colour changes were measured after 1, 3, 7, 14, 21, 30, 45 and 60 days of immersion. Results: The samples immersed in coffee solution changed from S1 to S2, whereas samples in tea solution changed from S1 to S3. Additionally, samples in red wine changed from S1 to S4, as observed using the Valplast colour tone guide. The highest reflection measured using spectroscopy was 65.146 at 385.19 nm of the control samples, whereas the lowest reflection was 1.974 at the wavelength of 385.97 nm on the samples immersed in the red wine. Conclusion: The most significant difference can be observed in the red wine group, followed by samples in tea and coffee solutions. Moreover, increasing the immersion period causes increasing staining effect of the denture.