Abstract: Preparation of semi-solid fats by chemical interesterification of blends with different weight percents from beef tallow, sunflower oil and soybean oil has been investigated. Blends of 25-70% beef tallow with sunflower and soybean oils have been chemically interesterified under these conditions: (temperature: 100-110°C, time: 60 min under 150 mmHg vacuum and adding 0.5 wt% of sodium methoxide as catalyst). Interesterified products were analyzed for melting point by wiley and capillary methods, iodine value by Hanus method, and SFC in 10, 20, 30 and 40°C by NMR method. Interesterified blends of 25% tallow and 75% sunflower oil got melting point and iodine value confirmed with national standard no. 143 of Iran for margarine, in addition to low SFC in 40°C. Interesterified blends of 30-70 wt% tallow with sunflower and soybean oils got melting point and iodine value confirmed with national standard no. 156 of Iran for confectionary fats. Interesterified products contained at most 2.1% trans-fatty acids that derived from the tallow fraction which originally contained 3.4% trans-fatty acids resulted from microbial hydrogenation in rumen.