The invention provides a heat reservoir exploitation nanometer material and basalt fiber composite cement based well cementation material. The heat reservoir exploitation nanometer material and basalt fiber composite cement based well cementation material is prepared from water, G grade oil well cement, an additive, basalt fiber, a nanometer material, an early strength agent, and a water reducing agent; the water/solid ratio (the ratio of the weight amount of water to the total weight amount of the G grade oil well cement and the additive) is controlled to be 0.5-0.8; the solid/solid ratio (the ratio of the weight amount of the G grade oil well cement to the weight amount of the additive) is controlled in a range selected from 9:1, 8:2, 7:3, 6:4, and 5:5. According to the heat reservoir exploitation nanometer material and basalt fiber composite cement based well cementation material, at different high temperature conditions, the optimized formula possesses appropriate fluidity, pumpable time, and setting time; mass loss is low; an obtained solidified body possesses excellent ratio of compressive strength, and ratio of static-dynamic moduli; an obtained well cementation material possesses high strength, toughness and excellent deformation capacity even under high temperature conditions; and problems in the prior such as difficultly controlled fluidity at high temperature environment of common cement based well cementation material, reduced strength, and brittle failure are solved effectively.