In this research, quantitative and qualitative analysis of silica from acid-treated rice husks were investigated. The type of acids were HNO3 HCl and H2SO4, concentrations of 1 3 5 and 7 N and mix acid of HCl:H2SO4 concentration ratio 1:1, 1:2, 1:3, 2:1,2:2, 2:3, 3:1, 3:2 and 3N:3N. The qualitative analysis of silica content was done by molybdenum blue method. The most effective acid was 7N HNO3 with percentage of silica of 99.95±0.01 %wt. The concentration decreases when the concentration of acid decreases. The mix acid of HCl:H2SO4 at concentration ratio 3:3 the percentage of silica 99.95±0.01 %wt. The quantitative analysis using X-ray Diffraction and Infrared Spectroscopy Techniques proved that the product was amorphous silica