Flowers of butterfly pea (Clitoria ternatea Linn) contain anthocyanins. The color of anthocyaninschange according to the pH solution.The aim of this study is to determine the application of butterfly pea extract as an indicator of acid-base titration. The results showed that the butterfly pea extract has the refraction index from 1.382+ 0.25 to 1.390+ 0.30, specific gravity from 0.975 + 0.20 to 0.993+ 0.25, maximum wavelength at 572and 614 nm, and discoloration from violet to blue at pH 4, blue to green at pH 9, and green to yellow at pH 12. We concluded that the butterfly peaextract can be applied as an indicator of acid-base titration.