Growth stresses in thin metal films on a substrate are important for integrated circuit device fabrication and reliability. The development of growth stress in blanket CVD-WGex films deposited by GeH4 reduction of WF6 is studied by in situ wafer curvature measurements. Depending on process conditions, the growth stress varies from 600 MPa tensile in β-WGex films deposited at low temperatures (T < 400 °C) to 400 MPa compressive in α-WGex films deposited at high temperatures (T > 400 °C). At very low temperatures amorphous WGex films grow without significant stress. Development of tensile growth stress is favoured by low temperatures and high growth rates, whereas development of compressive growth stress is favoured by high temperatures and low growth rates. Although the material properties of CVD-WGex films depend on process conditions, the development of growth stress in these films shows a dependence on deposition temperature and growth rate which is similar to pure α-W films deposited by H2 reduction of WF6. The results will be discussed in view of a model which has recently been put forward to explain development of growth stress in polycrystalline metal films on a substrate.