The optical and thermal properties of CdTe quantum dots (QDs) of different particle sizes are measured using photoacoustic technique (PA). CdTe QDs were synthesized using the chemical deposition method. The PA spectra show a blue shift as the sizes of CdTe QDs decrease which is in close agreement with that obtained by UV-Visible spectrophotometer. The sizes of the nano-particles were estimated using effective mass approximation (EMA) model, and ranged from 2.13 nm to 2.43 nm. The estimated values are comparable to those obtained by transmission electron microscope (TEM) and x-ray diffraction (XRD). The thermal diffusivity (D), thermal effusivity (e), and thermal conductivity (k) of all CdTe samples were also studied by PA technique. The determined values of D, e and k are at least one order of magnitude larger than the bulk value.