Alloy films of Mo and simple metal elements M(M=Ag, Mg, Sn, Sb, Bi, and Ge) have been produced by coevaporation method on substrates kept at about 80 K and their structure and electrical resistivity have been measured. The Mo‐Sn and Mo‐Sb films are found to be amorphous superconductors with a superconducting transition temperature of about 6 K at most. The Mo‐Bi films are also superconductors but crystalline; they show the same x‐ray diffraction pattern as that of hcp Bi. The upper critical fieldHc2has been measured for Mo‐Sn and Mo‐Sb films. TheHc2increases linearly with decreasing temperature down to 1.5 K. The value ofHc2extrapolated to 0 K is found to exceed the paramagnetic limit.