Thermal conductivity (TC) of potato was calculated from heat penetration into cylindrical samples between 50 and 100°C. TC ranged from 0.545 to 0.957 W/m°C for potatoes (cv Kennebec) specific gravity 1070 kg/m3 and moisture 80%. Experimental values agreed with reported values. TC, k, varied with temperature in a quadratic polynomial form, and an empirical relationship was estimated. A model based on the concept of thermal resistances in parallel was compared with experimental results. These were used in a heat transfer model that simulated potato frying. Measured and simulated time-temperature curves showed good agreement.