To investigate the shock initiation characteristics of the insensitive aluminized melt-cast explosives， a one-dimensional Lagrangian test system was established with the manganin piezoresistive pressure gauges and the loading technique of chemical explosion. The shock initiation process of an aluminized DNAN-based melt-cast explosive was measured， and the growth histories of pressure were obtained under different loading pressures. By virtue of the mesoscopic model of reaction rate of the aluminized melt-cast Duan-Zhang-Kim （DZK） ， the parameters of the aluminized explosive were determined and then the shock initiation process was simulated numerically. It is found that the higher the loading pressure is， the faster the detonation grows inside the aluminized explosive. In the shock initiation of the aluminized melt-cast explosive， the reaction degree and reaction rate are low near the leading wave front. However， the reaction rate of explosive after wave increases continuously and reaches the peak value in a while with the ignition reaction and the accumulation of chemical reaction Furthermore， compared with the growth history of particle velocity， those of pressure involve more detail of the growth of reaction rate， which are more suitable to be used in validating the reaction rate models and determining the parameters of reaction flow models.