Physical/mechanical properties of various cured allylamine-adducted bismaleimides (A-BMI), such as allylamine-adducted 4,4’-bismaleimidodiphenylmethane (A-BDM), and allylamine-adducted 4,4’-bismaleimidodiphenylether (A-BDE) were investigated and correlated to their morphology. In the previous study, two types of the curing reactions were found : one is the homopolymerization through the opening of double bonds in the maleimide groups and the other is the reactions between allyl groups and benzene rings. Dynamic mechanical analysis and scanning electron microscopy of cured A-BMI indicate that the network produced by homopolymerization is immiscible with that produced by the other reactions. The glass-transition temperature (T(g)) of the former network is lower than that of the latter. In addition, the 50%A-BDM prepared by reacting BDM with 50 mol% allylamine has the optimal physical/mechanical properties after cure, such as the highest T(g) and the highest flexural strength and modulus among the A-BDM. Moreover, the decomposition temperature of 50%A-BDM is 450-degrees-C, only about 40-degrees-C lower than that of the pure BDM.