The present article deals with colloidal quantum dots (QDs) synthesized in an aqueous medium using thioglycolic acid (TGA), L-cysteine (L-cys) and mercaptoethylamine (MEA) as stabilizers. In contrast to high-temperature synthesis in an organic medium, this method of synthesis enables us to skip an additional time-consuming stage of hydrophilization of QDs. The resulting CdTe QDs were studied by spectroscopic methods of analysis. In the absorption spectra of the QDs there is an exciton peak which corresponds to the minimum energy required to form excitons in the QDs. The average size of the QDs, which is about 3-4 nm, was calculated based on the position of the exciton peak. The zeta potential of the QDs was measured and the results were compared with literature data.