In this work, an experimental system based on digital real-time holographic interferometry for measuring the mass diffusion coefficients of fluid is introduced. The method of processing interference fringe hologram is also introduced thoroughly. By uncertainties analysis and experimental veri. cation, the accuracy of this system is validated. The experimental uncertainties in temperature and mass diffusion coefficient are estimated to be no greater than +/-0.16 K and +/- 0.2%, respectively. On this basis, mass diffusion coefficients of two fuel additives: 1,2-dimethoxyethane (ethyleneglycol dimethyl ether, GDME) and 2-methoxyethyl ether (diethylene glycol dimethyl ether, DGM) in air were measured at T (278.15-338.15) K under atmospheric pressure, and polynomial was fitted by the experimental data. (C) 2009 Elsevier Ltd. All rights reserved.