Device for performing deep drillings, especially geothermal, may include a surface base, a borehole in a geological formation, filled with fluid, and a robotic multi-functional underground drilling platform, which contains especially a block (2) for crushing rock (1), a block for continuous formation of casing profile, a block of casing as transfer and transport infrastructure, a block (16) of transport container, a control and communication block (39), an energy block (4), a block of operating transport containers, and a block of removing and loading rock (1) from the place of crushing. The block (2) for rock crushing may be interconnected with block of removing and loading rock (1) from the place of crushing by means of water channels, ensuring removal of the crushed rock 107. The block of removing and loading rock (1) from the place of crushing may be interconnected with block (16) of transport container by means of water channels. The block of casing as transfer and transport infrastructure may be connected to block of continuous forming the casing profile by means of moving formworks.