The Liverpool striekr, on loan at The Trotters, was claimed to have spat at Birmingham fans after scoring the first goal of the game.
But CCTV footage revealed that the claims were inaccurate.
"Bolton Wanderers Football Club has been in contact with Birmingham City today regarding the alleged spitting incident involving El-Hadji Diouf," said a club spokesman.
"Birmingham City confirmed that they have not received any complaints and the stadium's CCTV system has no evidence of the allegation.
"Both clubs will not be taking further action and the matter is now closed."
