Proton plays a key role in the interface-trap formation that is one of the primary reliability concerns, thus learning how it behaves is key to understand the radiation response of microelectronic devices. The first-principles calculations have been applied to explore the defects and their reactions associated with the proton release in α-quartz, the well-known crystalline isomer of amorphous silica. When a high concentration of molecular hydrogen (H 2 ) is present, the proton generation can be enhanced by cracking the H 2 molecules at the positively charged oxygen vacancies in dimer configuration. If the concentration of molecular hydrogen is low, the proton generation mainly depends on the proton dissociation of the doublyhydrogenated defects. In particular, a fully passivated E 2 center can dissociate to release a proton barrierlessly by structure relaxation once trapping a hole. This research provides a microscopic insight into the proton release in silicon dioxide, the critical step associated with the interface-trap formation under radiation in microelectronic devices.