The efficient removal of the fine oil droplets from a large amount of water produced by oil and gas production is a challenge faced by industries not only for environmental concerns but also for cost reduction. Although much effort has been made on developing various separation technologies, we still lack an adequate method to achieve desirable results. The nanoengineered advanced materials could play an important role in achieving the needed breakthrough on the effective removal of fine oil droplets from industrial wastewater. Herein, we report an amphiphilic Janus porous nanocomposite, which consists of oleophilic MoS2 nanospheres that are embedded within the hydrophilic three-dimensional (3D) reduced graphene oxide framework. The Janus MoS2/rGO nanocomposite is synthesized via the hydrothermal process. Our experiments confirmed that this Janus nanocomposite demonstrated 98.56% removal of fine oil droplets from water within 3 min, with remarkable regeneration and recycling ability. This excellent performance is attributed primarily to its Janus structure that offers amphiphilic surface property and high surface activity to effectively enhance the adsorption of oil droplets in the oil and water emulsion environment. These findings hold promise for the next-generation Janus nanocomposite-based technology aiming removal of fine oil droplets from oil- and gas-produced water in the energy industry.