A novel determination of solution density based on fiber refractive index sensing principle is first proved and studied in this paper.This method is suitable for the determination of solution density with known solute.Refractive indices of the NaCl and KNO 3 solutions with different concentrations at constant temperature(20 ℃) were measured respectively by applying this method.The linear relationship between refractive index and solution density is found.So solution density can be determined if ...