Mike 'The Situation' Shuns Alcohol in 'Jersey Shore' Reunion's First Night Out

Mike "The Situation" Sorrentino went booze-less during the "Jersey Shore" cast's first official night out.

Paps got Mike out Tuesday night with the rest of his GTL crew at a South Beach club, and he was clutching a Red Bull can the entire time.

Meanwhile, Pauly D and co. definitely partied it up and had bottle service at their table -- but the Sitch went dry throughout the night.

In case you're wondering, Mike's no-booze policy doesn't appear to be tied to his tax evasion case -- in which he just pled guilty last week, and is set to be sentenced later this spring.

On the contrary, Mike's said he's been "100 percent" sober since 2015 after battling a Rx drug addiction.