The City boss threw his scarf to the ground and shouted at fourth official Martin Atkinson after a challenge by a Liverpool player went unpunished.
Referee Anthony Taylor spoke to Guardiola, who apologised for his actions.
The Spaniard has been given a stage one warning under FA regulations. If he receives three more warnings, it will result in a one-match touchline ban.
Manchester City ran out 2-1 winners on Thursday to cut Liverpool’s lead at the top of the Premier League to four points.
Guardiola’s side face Rotherham United in the third round of the FA Cup on Saturday.