Well-controlled cubic nanocrystal of TMA-A zeolite with a size of 60~100 nm were synthesized by a hydrothermal method in a solution having a Al(i-pro)3 : 2.2 TEOS : 2.4 TMAOH: 0.3 NaOH : 200H2O composition. The single TMA-A nanocrystals has an average lattice constant of 24.61 Å having a surface area of 742.36 m2/g. Thermal treatment of TMA zeolite crystals results in the formation of an amorphous above 900oC. Environmental scanning electron microscopy (ESEM). high resolution transmission electron microscopy(HRTEM), X-ray powder diffraction(XRD), fourier transform infrared(FT-IR) spectroscopy, DTA/TGA and BET analysis were used to characterize the initial materials and the obtained products after various heat treatments.