In the present work, sixteen Mn-In alloys were investigated experimentally by means of thermal analysis and X-ray diffraction techniques. The temperatures of the invariant reactions and liquidus in the Mn-In binary system were determined. Based on the experimental results obtained in the present work and the critical review of the available experimental data from the published literature, the Mn-In binary system was assessed thermodynamically using the CALPHAD method. The solution phases including liquid, alpha-Mn, beta-Mn, gamma-Mn, delta-Mn and tetragonal_A6(In), are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich-Kister polynomial. The intermetallic compound, InMn3, is treated as a stoichiometric compound. A set of self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Mn-In binary system can be used to reproduce well the phase equilibria and thermodynamic data. (C) 2015 Elsevier B.V. All rights reserved.