High-quality CdSe quantum dots have been synthesized through an organometallic method with cadmium methoxide as a cadmium precursor. Without any size sorting, the FWHM (full width at half-maximum) in PL spectra almost for all CdSe samples is less than 30 nm and only 22 nm from the best sample. The emission peaks with different particle size in toluene can be tuned from 478 to 654 nm corresponding to a color change from blue-green to red.