An all solid state battery includes: a battery body including an electrode assembly having first and second surfaces in a first direction, third and fourth surfaces in a second direction, and fifth and sixth surfaces in a third direction, and including a solid electrolyte layer and a cathode and an anode; a first connection portion; and a second connection portion disposed on the electrode assembly. The first connection portion includes a first current collecting electrode and a first protection portion, the second connection portion includes a second current collecting electrode and a second protection portion, and the first current collecting electrode is drawn out to one surface of the first connection portion in the third direction and the second current collecting electrode is drawn out to one surface of the second connection portion in the third direction.