The purpose of this study was to study the effects of salt natural geothermal water (SNGW) treatment on the physical, mechanical, shrinking and swelling properties of wood materials from two pine species. This study used the SNGW of Eynal, citgol, and Nasa from Kutahya in Turkey on sapwood samples of black pine (Pinus nigra Arnold.) and Brutia pine (Pinus brutia Ten.). The absorption, retention, density, moisture content, modulus of rupture (MOR), modulus of elasticity in bending (MOE), compression strength parallel to the grain (CSPG), shrinking, and swelling values were measured for the treated and non-treated wood samples. The results showed that the absorption and retention values increased by depending on the concentrations of the dissolved salts in the SNGW used. In addition, the density and moisture content values of the SNGW-treated pine wood species were significantly higher than those of the untreated wood, whereas the values of MOR, MOE, CSPG, shrinking, and swelling were lower. In general, the Eynal treatment had the highest effect on pine species' wood properties, whereas the Nasa treatment had the least effect.