Tooth color can change because of several factors that are needed for teeth whitening. Teeth whitening can be performed on vital and non-vital teeth. Home bleaching is a vital whitening treatment that many people choose because practice can be done at home. Bleaching agent used for home bleaching techniques is 10% -22% carbamide peroxide. However, carbamide peroxide has side effects on the oral cavity. So, several previous researches have examined natural ingredients that contain the ability to whiten teeth. One of them is 100% watermelon extract which is proven to whitenteeth by immersing. However, this method cannot be applied clinically, so the purpose of this research is to know the effect of watermelon extract on tooth discoloration with rub techniques application. This type of research is an experimental laboratory. 10 maxillary premolars were discolored which were divided into two groups (watermelon extract and 10% carbamide peroxide). Each group was given the treatment 3 hours per-day for 14 days. After the bleaching process, the teeth are cleaned and immersed in a solution of saliva. Before and after bleaching, they were measured with a shade guide and spectrophotometer. Data analysis used paired t-test and wilcoxon. The results of paired t-test on group 1 p=0.024 (p <0.05). The wilcoxon test results on group 2 with p=0.043 (p <0.05). Both have influence, but the application of 10% watermelon extract is lower than 10% carbamide peroxide. It can be concluded: 100% watermelon extract with rubbing techniques has an effect on teeth whitening. Although, lower than 10% carbamide peroxide