Even though Google shares fell 0.38 percent, a bigger drop in Exxon stock allowed the Internet giant to capture the second spot in market capitalization.
Google's market cap at the end of the trading day was $394 billion, compared to the $388 billion of ExxonMobil. Apple remained well ahead with a market capitalization of $472 billion.
Google briefly overtook Exxon during the trading session last Friday but Monday was the first time this was confirmed at the close of trade.
ExxonMobil shares fell 1.17 percent on Monday to $89.53, bringing its year-to-date loss to 11.5 percent.
Google, despite Monday's modest dip, is near its all-time high and has doubled in value since July 2012. The shares closed Monday at $1,172.93.
The California-based Internet group is the world leader in online advertising, its Android operating system has become the dominant platform for smartphones and is also gaining fast in tablet devices.