Phase equilibria in the Co-Cr-Nb ternary system were experimentally investigated by using back-scattered scanning electron microscopy, electron probe microanalysis, composition mapping and x-ray diffraction on equilibrated alloys. In this study, isothermal sections of the Co-Cr-Nb ternary system at 1000, 1100 and 1200 °C were determined. The intermetallic compounds Co7Nb6 and CoCrNb, together with their single phase regions were determined on all three isotherms, as well as three tie triangles involving the (Nb) + Co7Nb6 + CoCrNb, (αCr) + σ + CoCrNb and (αCo) + σ + CoCrNb phases. The current diagrams differed significantly from a previous isotherm reported at 1000 °C. The newly determined phase equilibria in the Co-Cr-Nb system may provide useful information for perpendicular magnetic recording materials and high-temperature alloys.