Measurements of the thermal conductivity of n-pentane performed for the first time, in a coaxial cylinder cell operating in steady state conditions are reported. The measurements of the thermal conductivity of n-pentane were carried out along nine isotherms in the liquid state and fourteen isotherms in the gaseous state. The present data cover the temperature range from 300 K to 620 K and the pressure range from 0.1 to 50 MPa. An analysis of the various sources of error leads to an estimated uncertainty of approximately +/- 1.5%. A comparison is provided with the previous experimental works. (C) 2017 Elsevier B.V. All rights reserved.