Abstract:X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM) and magnetic measurements as a function of applied magnetic field and temperature for In 1− Mn Sb (0.05 0.2) system are reported. Magnetic measurements performed at high and small magnetic field in ZFC and FC indicate the coexistence of ferromagnetic In 1− Mn Sb solid solution and two types of magnetic cluster: ferromagnetic MnSb and ferrimagnetic Mn 2 Sb. XPS valence band and Mn 2p core level spectra have confirmed the presence of MnSb and Mn 2 Sb phases. TEM images show some manganese antimonide phase microinclusions with dimension between (30-40) nm.