Bone defect is a common problem in the field of dentistry. The defect can be solved by tissue engineering. One component of tissue engineering is scaffold. Carbonate apatite is the main material used because it has an organic components similar to human bones. The carbonate apatite combined with gelatin and chitosan can be used as a scaffold for tissue engineering. The aim of this study is to know the exact ratio of the carbonate apatite, gelatin-chitosan (CA:Ch-GEL) scaffold on the compressive strength and porosity size as biomaterial candidates in tissue engineering. Scaffold was synthesized from CA:Ch-GEL with different ratios of 50:50, 60:40, 70:30 and 80:20 with freeze drying method. Fourier Transform Infared Spectroscopy (FTIR) was used CA:Ch-GEL scaffold functional group identification. Scaffold mechanical test was performed using an Autograph while a porosity test was performed using Scanning Electron Microscope. All data were analyzed by ANOVA followed by Tukey HSD test. Scaffold has a compressive strength ranges 4.02-11.35 MPa, with porous ranges 19,18 mm – 52,59 mm at 50:50, 60:40, 70:30 and 80:20 ratios. CA:GEL-Ch scaffold at all ratios can be used as biomaterials in tissue engineering.