Background: Saliva is a complex liquid secreted form salivary glands which serves as a protection of the oral cavity, digestion and performing a buffer role. Salivary pH will increase along with the increase in salivary flow rate. One of the factors that can cause an increase in salivary pH is the stimulation given by an orthodontic appliance in the oral cavity. Aim: To know the effect of removable orthodontic appliance on salivary pH. Method: The study was conducted on 20 subjects of removable orthodontic appliance users and 20 subjects of control at RSGM Universitas Muhammadiyah Yogyakarta. The research design used in this research is analytic observational with cross sectional approach. Result: The result showed that the average value of salivary pH on subjects of removable orthodontic appliance users is 7,905, however the average value of salivary pH on subjects of control is 7,350. The independent t-test analysis shows p value = 0,00 which means there is a significant result (p < 0,05) between the salivary pH of removable orthodontic appliance users and control. Conclusion: The conclusion of this research is that there is an effect of removable orthodontic appliance on salivary pH.