The densities, surface tensions and refractive indices of the 1, 3-propanediol+water system were measured at various 1, 3-propanediol concentrations and temperatures. Also, the data regression was done with simple polynomial equations for each experimental data set. The average absolute deviations (AADs) were found to be 0.123 % for density, 0.77 % for surface tension, and 0.045 % for refractive index.