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In this study, the properties of concretes containing silica fume (SF) at different substitution levels after exposure to sodium sulfate solution were investigated. For this purpose, 5%, 10% and 15% SF were used according to the cement weight. The mixtures were kept in Na2SO4 solution with 3%, 5% and 10% concentrations for 30, 60, 90 and 120 day periods. Compressive strength losses and expansion ratios of all mixtures after exposure to solution were determined. In addition, the slump values of the mixtures as fresh concrete properties were also measured. A superplasticizer was used especially in order not to decrease the slump values of SF added mixtures. Thus, there was no significant decrease in the slump values of the SFadded mixtures. The test results showed that the presence of SF had a positive effect on the strength loss caused by the sodium sulfate effect. The best resistance to sodium sulfate attack was obtained with 15% SF substitution; A strength loss of 3% to 8% was detected in a 120-day period and at all concentrations. In particular, the strength of the samples exposed to 3% concentrated solution increased at early ages (30 and 60 days). This can be attributed to the filling of the pore spaces by the expanding products and the thickening of the mortar matrix. While the relative residual compressive strength of the control sample kept in 10% concentration solution ranged between 94% and 77.95%, these values were obtained between 100.31% and 92.35% for the SD-15 sample. In addition, it was observed that the expansion values of the samples exposed to the Na2SO4 solution were similar to the compressive strength results. [ABSTRACT FROM AUTHOR]