Parker earned a split decision points win in Manchester, England on Sunday after being knocked down less than 10 seconds into the first round (NZ time).
In a tight fight that lasted 12 rounds, the former WBO world champion was the better of the two fighters in the second half, doing just enough to earn his fifth straight victory.
Parker won the fight 116-111 and 115-113 on two of the three judges’ scorecards, with the other judge scoring it 115-113 for Chisora.
The result extended the 29-year-old’s professional record to 29-2, with 37-year-old Chisora falling to 32-11.
The fight was Parker’s first since parting ways with longtime trainer Kevin Barry and teaming up with Irishman Andy Lee.