The lanky frontman was unveiled by the club on Monday afternoon, just over 48 hours after Amakhosi reached an agreement with Mamelodi Sundowns.
Kaizer Chiefs (@KaizerChiefs) December 18, 2017
Castro, 28, has been in the country for two-and-a-half seasons now, and he took the PSL by storm in his first few months with the Brazilians alongside Khama Billiat and Keagan Dolly.
He will be expected to hit the ground running when the league resumes early next year, with Amakhosi desperate to win at least one of the two trophies on offer for them this season.
Details of Castro's contract with Amakhosi have not been made public, but reports suggest that he has agreed a two-and-a-half-year deal.
Castro stopped training with Pitso Mosimane's side on Friday, as his move to Naturena appeared closer to completion.