The framework-substituted manganese beta zeolite was synthesized by an unseeded hydrothermal method, using manganese nitrate, colloidal silica, sodium aluminate, and tetraethylammonium hydroxide as raw materials. The optimized synthetic conditions were obtained by adjusting the key synthesis parameters, such as SiO2/Al2O3 ratio, TEAOH/SiO2 ratio, pH value, crystallization temperature, and SiO2/MnO ratio. The resulting samples were characterized by powder XRD, UV-vis spectroscopy, nitrogen physical adsorption, and ICP, which complementarily demonstrate the incorporation of manganese into the zeolite framework. Tested in hydroisomerization of n-heptane as a carrier for Pt catalyst, the Mn-incorporated sample showed a very high selectivity for isomerized products 94.7% with a high conversion of n-heptane 71.1% at 230 degrees C.