This is the first time that such a system has been deployed in Lithuania.
The ministry said in a press release that the Patriot system had been deployed for the Tobruq Legacy 2017 air defense exercise to be held in the county of Šiauliai between July 11 and 22.
The exercise in Lithuania will involve around 500 troops and some 30 air defense systems from Lithuania and another four NATO member states.
The Defense Ministry said that the deployment of the Patriot system "demonstrates strong US commitment to ensuring security in Lithuania and a high level of US preparedness to quickly deploy strategic capabilities in the region".
The US-organized Tobruq Legacy 2017 drills will also take place in the Czech Republic and Romania. The Lithuanian Air Force will take part in the annual exercise for the third time.
The Baltic countries' air defense is one of the region's weakest spots in terms of defense. Lithuania, Latvia and Estonia currently only have short-range air defense systems.
Lithuania this year expects to reach a final agreement with Norway on the purchase of NASAMS medium-range systems.