Effective thermal conductivity (K-eff) of nanocomposites containing thermally conductive AlN nanoparticles reinforced into HDPE is investigated. The morphology of the composites is characterized by SEM and HR-TEM. K-eff of the composites with various volume% loading of AlN (nano) is investigated by transient technique and display similar to 40% enhancement for HDPE/20vol.%AlN at 30 degrees C. K-eff data is examined in light of various semi-empirical models, which shows a fair correspondence with only Agari and Uno model. The analysis also indicates that conductive chains are formed in HDPE/AlN (nano) composites, in agreement with SEM and HR-TEM observations. The measured K-eff has also been analyzed using finite element based simulation assuming homogeneous distribution of AlN nanoparticles. The present analysis further confirms that FEM based simulation, considering the role of voids/pores present in the composites provides excellent agreement (similar to 1.2%) with the measured K-eff for HDPE/AlN (nano) composites. (C) 2016 Elsevier B.V. All rights reserved.