We report on a synthesis procedure to achieve site-selective growth of noble metal domains on CdSe nanoplatelets. The novel morphological properties of the resulting metal−semiconductor nanoheteroplatelets are characterized by transmission electron microscopy, UV−vis absorption, photoluminescence emission, X-ray photoelectron spectroscopy, and by X-ray diffractometry. By variation of the synthesis parameters, several different morphologies can be achieved: depending on the noble metal and the type of precursor, the growth of Au, Pt, and Pd domain takes place at the corners or edges, around or only at the two shorter edges of the rectangular sheet. This novel kind of hybrid nanoheterostructure might find future applications in photocatalysis, chemical sensing, or fabrication of photovoltaic devices.