Graphene-oxide nanocomposites have promising applications like chemical sensor, photocatalysts, fuel cells, super capacitors etc. and are useful for monitoring the toxicity, inflammability, and explosive nature of chemicals. Metal oxides like ZnO, TiO2, SnO2, when combined with graphene oxide in the form of nanocomposites have excellent potential for detecting trace amounts of hazardous gases and chemicals. ZnO-GO nanocomposites have various applications like gas sensors, humidity sensors, UV sensors, water purification, capacitors and optoelectronic applications. Various techniques have been used by researchers for the synthesis of ZnO, GO and ZnO-GO nanocomposites. This paper presents a comprehensive review of the available synthesis techniques, properties and applications of ZnO-GO nanocomposites.