Well-defined Au nanoplates have been mass-synthesized through a chemical method at high and low temperatures. A time-saving method for the fabrication of hexagonal Au nanoplates has been developed by modifying polyol process with the presence of binary surfactants. In general methods, most Au nanoplates are in regular shapes of triangle and hexagon. While Au nanoplates with novel shapes, involving star-like and shield-like and other novel polygonal, are found with introduction of obvious temperature variation in the early crystal growth stage. Structural studies demonstrate that the obtained Au nanoplates are single-crystalline with (1 1 1) planes as two basal surfaces. The formation of these new and well-defined Au nanoplates can be understood from the growth of (1 1 1) plane along <1 1 0>, <2 1 1> and other high-index directions. The ability to control the shape of Au nanoplates provides a great opportunity to systematically investigate the anisotropic growth of noble nanostructures. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.