Novel two-dimensional antimonene, is recently reported to be stable by first principles calculations Wang et al. [35]. Its thermal properties are now investigated using the phonon Boltzmann transport method. Specifically, the size and edge roughness effects on the thermal conductivity of antimonene allotropes, namely alpha-Sb and beta-Sb are determined. The semiconducting alpha-Sb and beta-Sb have the rectangular and hexagonal unit cells, respectively. We find that thermal conductivity increases with size, and decreases with the edge roughness of the antimonene allotropes. Higher thermal conductivity occurs for a-Sb, and its distinct characteristics in the in-plane acoustic branches are found to be associated with the anisotropic nature of the 2D lattice. (C) 2015 Elsevier B.V. All rights reserved.