The Assault kit is featured in Battlefield 3, functioning nearly identical to its Battlefield 2142 counterpart; a combination of the Battlefield 2 Assault and Medic. The assault is equipped with an assault rifle or an all-kit weapon, with the default weapons varying by faction.

The USMC assault wields an M16A3 and an M9, whereas the Russian Ground Forces assault wields the AK-74M and MP443.

The kit is initially equipped only with the medkit, but can quickly unlock other gadgets and weapons; the first unlock for the kit is the Defibrillator, which are the only option for the second equipment slot.

However, the medkit must be swapped out if the player wishes to wield either of the two underslung weapons, the M320 (or GP-30 if equipped as an underslung attachment on one of the Russian-made weapons) or the M26 MASS.