Melamine resin foam (Mfoam) is a porous heat-cured amino resin material with excellent flame retardancy, thermal insulation, and noise reduction capabilities. However, some fatal shortcomings like easy brittle breakage, easy powderization and poor toughness directly limit its wide application and further development. In this paper, hydroxypropyl acrylate (HPA) was used to participate in the synthesis of melamine resin oligomers (Moli) in order to link the vinyl group to molecular skeleton. As a result, both vinyl and hydroxymethyl active groups are present in Moli which provide Moli with the ability to perform free radical polymerization reaction and polycondensation polymerization reaction, named double polymerization reaction (DPR), and produce synergistic effects to form a structurally toughened melamine resin foam (TMfoam). The research shows that the scheme can effectively solve the problems of brittle breakage and easy powderization of Mfoam. And under apparent density (Ad) of 40 ± 2 kg/m3, the prepared TMfoam has good toughness, with the bending strength of 405.2 kPa, the compression strength of 352.5 kPa, and the pulverization rate of 1.18 %. Meanwhile, the combustion grade of the TMfoam can reach to B1 grade, and the thermal conductivity is 0.0328 W/(m·K). Also the absorption coefficient of TMfoam can reach up to 0.92 under frequency of 3045 Hz. All the facts indicate that the DPR showed good synergistic effect during the forming and setting stages from Moli to TMfoam. At the same time, the bubble chamber of TMfoam changes from metastable state to stable state, and its strength and toughness are significantly improved in step. This research has great and practical significance for expanding the wide application of Mfoam type materials.