Resistive critical current densities, critical fields, and normal‐state electrical resistivities were obtained at 4.2 °K for 55 alloys in the Nb‐Ti‐Zr ternary alloy system, excepting Ti‐Zr binary compositions. The resistive critical field as a function of ternary composition has a saddle point between the Nb‐Ti and Nb‐Zr binaries, so that ternary alloying in this system is not expected to result in higher critical fields than the binary alloys.