It was 'Side's sixth pre-season game at Redbridge Sports Centre this summer and Michael Walther's men took the lead on 16 minutes.
Barking hit back and equalised through Taylor Tombides on 35 minutes, before the same player put Glen Golby and Justin Gardner's team ahead three minutes later.
Michael Pindy made it 3-1 to Barking on 53 minutes before Jay Knight scored three minutes later to increase the advantage.
'Side though would grab the final goal of the game, with their second coming on 67 minutes.