We report the synthesis and characterization of crystal-like structurally well-ordered ethylene-containing hybrid mesoporous organoaluminosilicate materials, which exhibit molecular-level periodicity in the pore walls and enhanced hydrothermal stability. Distilled 1,2-bis(triethoxysilyl)ethylene (BTEE) was used as the organosilica precursor, aluminum isopropoxide as aluminum source, and cetyltrimethylammonium bromide as template. The materials are structurally well-ordered and exhibit high surface area (> 1300 m(2)/g) and pore volume (> 1.10 cm(3)/g). The presence of molecularly ordered ethylene groups was confirmed by powder X-ray diffraction, Si-29 and C-13 MAS NMR, and Raman spectroscopy. The ethylene groups are thermally stable up to a temperature of 300 degreesC. The presence of ethylene groups enhances the hydrothermal stability in boiling water of both organosilica and organoaluminosilicate materials. The organoaluminosilicate materials possess a bifunctional character arising from the presence of both tetrahedrally coordinated Al and molecularly ordered ethylene groups in their frameworks.