Captain Daniel Mavimbela said the man was arrested in Mamelodi, northeast of Pretoria, on Friday. This was after a series of investigations were conducted.
The body of the woman, 28, from the Free State, was discovered inside the building of the Department of Agriculture, Forestry and Fisheries in Pretoria last year December.
Missing reports of her begun on December 22 when no one could trace her whereabouts, after she allegedly disappeared from work during a tea break.
Mavimbela said the woman was employed by a company that rendered a private service within the department.
Her body, in a decomposed state was discovered by a security guard on December 28, during the department’s Christmas break.
The man is set to appear in the Pretoria Magistrate’s Court on Monday and he will face murder charges.