reinforcement aerated thermal insulation plate of the present invention during shaping in step 4 a shaping temperature is 160 u00b0 c 180 u00b0 c a shaping pressure is 2 mpa 3 mpa and a shaping time is 5 10 min during steam curing in step 5 a steam curing time is 10 12 h and an indoor steam curing temperature is kept at 100 170 u00b0 c a preparation process of fiber reinforcement aerated thermal insulation plate comprises the following process steps weighing the raw materials according to the following weight portion proportion 80 kg fly ash 30 kg expanded perlite 10 kg haydite 10 kg vegetable fiber 5 kg winnowing beads 5 kg sepiolite 3 kg sodium fluorosilicate 3 kg calcium formate 2 kg foaming agent 0 1 kg triisopropanolamine loeate and 0 1 kg dimethoxy ethane a removing impurity part of the vegetable fiber raw materials cutting the vegetable fiber raw materials into 20 cm small segments adopting an air flow type drying machine to dry the vegetable fiber raw materials till moisture of the vegetable fiber raw materials is below 0 1 and then cutting the vegetable fiber raw materials into 3 cm for reserve b putting the fly ash expanded perlite haydite and sepiolite into a pulverizer for pulverization and then filtering through a 100 mesh for reserve 2 mixing putting the fly ash expanded.