The charge relates to his language and behaviour towards match officials following the 3-3 Championship draw against Reading at the Madejski Stadium on November 13.
Lambert was unimpressed by the performance of referee Michael Oliver, whom be branded "pathetic" after sending off captain Grant Holt with City leading 3-1 before the Scot was himself banished to the stands late on.
Holt had his red card overturned on appeal but Lambert, who served a one-match touchline ban last season after the controversial 3-1 defeat at Tranmere, did not avoid punishment.
It means he will be in the stands for Sunday`s East Anglia derby with Ipswich at Carrow Road and for the trip to Derby on December 4.
Source: PA
Source: PA