The effect of the substitution of Cu for Ni on the magnetoresistance behaviour and the magnetocaloric properties of the Ni 50 Mn 34 In 16 alloy has been investigated. The (Ni–Cu) 50 Mn 34 In 16 alloys crystallize in the cubic L2 1 structure in austenite phase. While the M s temperature is about 160K for the Ni 47.5 Cu 2.6 Mn 34.0 In 15.9 alloy, the martensitic transition is not observed for Ni 45.5 Cu 4.6 Mn 33.8 In 16.1 alloy. To estimate the magnetic entropy change of the Ni 47.5 Cu 2.6 Mn 34.0 In 15.9 alloy, the magnetization measurements as function of magnetic field are performed by continuous and noncontinuous heating methods. The Ni 47.5 Cu 2.6 Mn 34.0 In 15.9 alloy shows the magnetostructural transition whose irreversible ratio is about 50% at 160K. The magnetocaloric effect strongly depends on the sample history due to the occurrence of the irreversible magnetostructural transition. For the magnetic field change of 2T, giant magnetoresistance value is about −68% that is rather big among the similar bulk alloys.