A chemical bleaching materials which widely used in dentistry have some effects. Sensitive teeth is one of the side effects from using a chemical bleaching materials. Starfruit can be used as an alternative bleaching material because these fruit contain of oxalic acid which is able to whiten the teeth. Oxalic acid whiten the teeth by oxidized the teeth colour pigments. The concentration of the bleaching materials is an important factors that affect the process of teeth whitening Objective. The purpose of this study was to knowing the effect of difference in concentration of starfruit extract towards teeth colour change Method. This study is experimental laboratory (in-vitro). The sample consisted of 15 premolar teeth. All the teeth soaked in tea solution for 12 days to obtain the discoloration effect, after that colour of the teeth was measured by using Spectrophotometer. Sample divided in 3 groups each group consisted 5 teeth. The teeth soaked in starfruit extract with different concentration 50%, 75%, and 100% for 88 hours. Tooth colour was measured by using the Spectrophotometer. Data analysis using Paired T-test, One Way Anova, and LSD (Least Significance Difference). Result. The result from Paired T-test was show that the score p=0,000 (p<0,05) for all concentration that mean the starfruit extract has an influence to discoloration of the teeth become brighter. The result from One Way Anova was show a score p=0,000 (p<0,05) for concentration 50%, 75%, and 100%, which mean there are significant of different concentration of starfruit extract has influence to brighter colour of the teeth. The result from LSD test was show there are significant in every each group except 50% and 75% concentration of starfruit extract. Conclusion. There are effects of starfruit extract concentration towards teeth colour change that is the higher the starfruit extract concentration, the effectiveness of teeth whitening is getting better. 100% extract concentration is the best result compared to 50% and 75% extract concentration in whitening the teeth.