Metal-oxide heterostructures are very important materials for developing various toxic gas/chemical detection sensor systems. However, the major factors, such as sensitivity, selectivity, stability, response, and recovery times of the sensors, still need to be optimized for practical technological applications. Low-dimensional materials have shown tremendous potential to solve majority of the critical issues due to their surface chemistry than that of their bulk form. In this paper, the role of nanostructured n-ZnO/p-NiO heterostructure as room temperature (RT) ammonia sensor has been investigated. Toward this paper, the electrospinning method was employed to prepare heterostructure metal-oxides blended with polyvinyl alcohol (n-ZnO/p-NiO) nanofibers. The systematic characterizations of the obtained n-ZnO/p-NiO heterostructure were performed using X-Ray diffractometer, scanning electron microscope, and photoluminescence spectrophotometer. Furthermore, the RT ammonia sensing characteristics were investigated.