Half-Heusler (HH) compounds such as ZrNiSn and FeVSb are potential thermoelectric materials due to low cost and non-toxicity. However, the thermal conductivity, κ, of HH compounds is large and reduces the thermoelectric figure of merit, ZT. An amorphous microstructure may be helpful to reduce the κ. In this work, we synthesized amorphous Zr-Ni-Sn (J Electronic Materials, 44, 1957-1962, 2015) and Fe-V-Sb films by magnetron sputtering. The HH films were sputtered using self-made targets and the sputtering parameters such as pressure and power were optimized. Then, the microstructure of the HH films was studied by HRTEM and XRD and an amorphous structure was identified. The Seebeck coefficient, electrical conductivity, and κ were measured. The amorphous structure greatly reduced the κ to 1-2 W/(mK), which was one order less than that of bulk HH compounds. The power factors of the films were 2-3 mWK-2m-1. Therefore, amorphous HH films are promising thermoelectric materials.