Hydrogen varies its stable state in accordance with its temperatureand density. Though molecular gas is stable in the environment, themonatomic state is stable in high density ranges of more than about1 g cm−3. Suchdense hydrogen has many aspects never seen in the molecular state. For example, in the range over about108 K temperatureand over 103 g cm−3 density, great efforts are being made to realize inertial confinement fusion(ICF). Additionally, in the range of temperature lower than about105 K and of densitymore than 104 g cm−3 pycno nuclear fusion is supposed to occur. Here for the first time we have derived theexpression for the Debye screening length of the interionic potential, taking into accountcorrelated electron pairs, and investigated the nuclear reaction rate in superconductive solidmetallic hydrogen. It is revealed that the screening length is shortened by correlatedelectron pairs that follow the Bose–Einstein distribution in the superconductive state. Thebosonization increases the number of lower energy states of the electrons to increase thescreening effects on the potential with decreases in the temperature, resulting in asignificant enhancement of the nuclear reaction rate by more than 10 orders ofmagnitude.