A field experiments was conducted at MPKV., Rahuri to study the effect of saline water and gypsum on chemical properties of soil. The treatments S₁, S₁, S₂ and S₃ in which saline water and canal water used for irrigation to sunflower and gypsum was applied as an amendment. The salinity of all canal water was 0.39 dSm^-1 (treatment S₀) and that of all saline water the ECsw was 2.20 dSm^-1 (treatment S₁). The salinity levels of treatment S₁ and S₂ were made by conjuctive use of 1 saline water followed by 1 canal water and 2 saline water followed by 1 canal water respectively. Gypsum was applied @ 923 g/plot in S₁ and S₂ treatment. The soil pH, ECe, Na+, Mg²⁺ and SAR of saturation paste extract increased under saline water irrigation treatment while Ca²⁺ content decreased. The soil pH increased from 8.09 to 8.49, ECe 0.92 to 1.86 dSm^-1, Na 17.93 to 20.2 meL^-1, Mg 6.53 to 18.29 meL^-1 and SAR 2.21 to 4.69 meL^-1. The Ca²⁺ content decreased from 19.03 to 18.10 meL^-1. Soil pH, ECe, Na+, Mg²⁺ and SAR of saturation paste extract decreased while Ca²⁺ content increased with application of gypsum. Soil pH decreased from 8.09 to 7.82, ECe 0.92 to 0.71 dSm^-1, Na 7.93 to 7.25 meL^-1, Mg 6.53 to 5.88 meL^-1 and SAR 2.21 to 2.03 meL^-1. The Ca²⁺ content increased from 19.03 to 19.49 meL^-1. Soil crust strength was increased from 1.89 to 2.16 kg/cm² with increase in the salinity of irrigation water from 0.39 to 2.20 dSm^-1. Application of gypsum decreased the soil strength from 1.89 to 1.61 kg/cm². The yield of sunflower was decreased significantly from 1028 kg to 723 kg ha^-1 with increase in the salinity of irrigation water. The highest sunflower yield of 1437 kg ha^-1 was observed under treatment S₂ where gypsum was applied with saline irrigation water.