World Series -- Boston Counterterrorism ... In Your Face

The FBI, the Boston PD, the Dept. of Homeland Security ... just about every law enforcement group in the land will be patrolling the Boston area in force during the World Series in an effort to thwart a possible terrorist attack, TMZ has learned.

In the wake of the Boston Marathon bombing back in April, the city is taking every possible measure to make sure people are safe when the Series comes to Beantown on Wednesday.

TMZ spoke with multiple law enforcement agencies ... who told us the Boston PD will be in charge of coordinating the plan to keep the area safe.

The police presence will be huge -- and in your face -- with uniformed and undercover officers, bomb-sniffing dogs, snipers and other counterterrorism measures in place.

Still, cops tell us ... as usual, they count on the people to provide tips if they see anything suspicious. See something, say something.