The Metropolitan Police said Simon Finch, 49, from Swansea, was alleged to have accessed the information as a civil servant or government contractor.
He has been bailed to appear at Westminster Magistrates’ Court on 9 October.
A Counter Terrorism Command probe was launched around 28 October 2018.
Under the 1989 act, a disclosure is considered damaging if it “damages the capability” of the Armed Forces, leads to loss of life, injury to its personnel or endangers UK interests abroad.
A Ministry of Defence spokesman said: “We are aware of proceedings involving an individual who has been charged with breaching the Official Secrets Act.
“This is a police matter.”