Abstract: In recent years, pericarp (peel) of Garcinia mangostana (known as mangosteen) has been used as a traditional medicine for the treatment of oral malodor, mouth apthae and chronic ulcer or as anti-inflammatory agent and antibacterial substances. This study was conducted to investigate the effect of immersion in pericarp of G. mangostana solution on tooth surface color. Fifteen premolar teeth were immersed in 1, 2 and 3% pericarp of G. mangostana solution (n = 5). Duration of immersion was 60 min (equal to 1 min day-1 gargling for 2 months), 120 min (equal to 4 month gargling) and 180 min (equal to 6-month gargling). The specimen’s color were measured with CIEL*a*b* method (intraoral spectrophotometer, Vita Easyshade, USA). There were significant changes of lightness (L*) and redness (a*) of specimen after immersion in 1, 2 and 3% solution of G. mangostana pericarp for more than 60 min (p>0.05). The tooth color change (ΔE) was clinically perceptible and beyond clinical tolerance (ΔE>3.50) in all immersion time. It was concluded that G. mangostana solution can affect tooth color and was clinically unacceptable. The highest color change was in group that immersed on 2% mangosteen solution for 180 min (ΔE = 20.35), it was equal to gargling for 6 months/day/minutes.