The Ni-W and Ni-Co-W alloys have been electrodeposited on copper substrates from a citrate bath. The effects of pH values on the microstructure, soft magnetic properties and mechanical behaviors of the electrodeposited alloys have been investigated by XRD, SEM, EDX, VSM and Vickers microhardness measurements. The results show that the pH value affects the microstructure of both of the alloys. The microstructure of the alloys shows an amorphous structure if the pH value is less than 9, and a nanocrystalline structure with average grain size of 5 nm at the pH value of 9. The Vickers microhardness of Ni-Co-W electrodeposits reaches 10.5 GPa in the case of nanocrystalline structure. The coercivity reaches the minimum of 23×79.6 A/m when the pH value is 6. The soft magnetic properties and microhardness of electrodeposited Ni-W alloys are improved by Co adding