The Gunners are four points off the pace of Premier League leaders Manchester United and Manchester City on 10 points, with the Blues a point behind on nine.
Arsene Wenger’s charges suffered a 4-0 defeat to Liverpool in August but redeemed themselves with a 3-0 win last week against Bournemouth.
They followed that up with a positive 3-1 win over Bundesliga side Cologne on Thursday.
Consistency will be key and Cech insists that back-to-back Premier League wins will help his side stay in contention at the top of the table.
“Chelsea have the same objective as us, they want to challenge for the title so it’s a big game this weekend.
“If we want to be close to the top of the table after two defeats then we have to win the big games and this is the first opportunity for us to do so,” said the 35-year-old to Sky Sports.
Arsenal have not beaten their west London rivals at Stamford Bridge since October 2011, but the Blues have won their last five home matches against them.
And with Eden Hazard having scored in three of his last four Premier League matches at home against the Gunners, manager Wenger’s defense will need to at their best.
“We played Chelsea in the Community Shield and in the FA Cup final last season, so we know we can beat them,” Cech added.
“They know they lost two games against us that they were not happy to lose, so this is something we have to use to our advantage.”