Gold nanoparticles (GNPs) have been widely used as one of the most versatile nanomaterials in a variety of fields such as catalysis, sensors and biomedicine, due to their unique physico-chemical properties which are highly dependent on the size, shape and local environment at the micro/nano scale.In colloidal synthesis of high-quality GNPs, the aqueous-organic phase transfers of metal nanoparticles in miscible two-phase systems, which usually necessitated the use of typical capping molecules, were frequently required and especially beneficial for morphology-controlled synthesis with special shapes, sizes and surface modifications.