The current study explores the presence of strong magnetoelectric (ME) coupling in a sputtered deposited NiMnIn/aluminum nitride (AlN) heterostructure on an Si substrate. The X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy results confirm the formation of a pure AlN wurtzite phase in the ME heterostructure. The magnetization vs temperature measurement shows the presence of the martensite transformation region of the NiMnIn/AlN heterostructure. The magnetic measurements exhibit the room temperature ferromagnetic nature of the NiMnIn/AlN heterostructure. The NiMnIn/AlN ME heterostructure was found to have a high ME coupling coefficient of ∼99.2 V/cm Oe at Hdc = 300 Oe. The induced ME coupling coefficient shows a linear dependency on Hac up to 8 Oe.