Goals from Alex Song, Cesc Fabregas and Theo Walcott in a nine-minute spell either side of half-time condemned Carlo Ancelotti's team to another defeat and they have now managed just six points from the last 24 on offer.
Branislav Ivanovic replied for the visitors but the damage was already done as Arsenal ended a run of five consecutive defeats against their London rivals to reclaim second place in the table above Manchester City on goal difference.
"The win had a double impact. First of all it keeps us in touch with the leaders and, secondly, it is the pyschological impact because we were questioned about our ability to win big games," Arsenal manager Arsene Wenger told reporters.
"We know that to beat the big teams at home will have an important impact on the league (title race)."
"The table is not good but this is the reality," said Chelsea manager Carlo Ancelotti. "We have to play better and wake up. I am not worried. I have to work and you will have to ask the owner (Roman Abramovich about my future)."
After an unofficial two-week "winter break" caused by the freezing weather conditions in Britain, both sides knew a win was needed to stay in touch with Manchester United.
If anything Chelsea had looked the more threatening early on with Didier Drogba, scorer of 13 goals in 13 appearances against Arsenal since joining Chelsea, rampaging forward to fire narrowly wide of Lukasz Fabianski's post.
Arsenal's home form has been an irritant this season with three defeats already at Emirates Stadium and there were anxious grumblings around the stadium as their pretty possession football offered little goal threat.
Michael Essien's attempt to win the ball in midfield inadvertently sent Walcott racing through on goal and the Engla
