An electronic device includes a first unit, a second unit, and a lock mechanism. The lock mechanism includes: an engagement projection provided on a third side surface of the first unit; a latch provided on a fourth side surface of the second unit, the latch being rotatable around a rotation axis provided perpendicular to the fourth side surface between a first rotational position where the latch does not engage with the engagement projection and a second rotational position where the latch is engageable with the engagement projection, and an urging member that urges the latch to be positioned at the second rotational position. The latch has an inclined part. When the latch is located at the second rotational position and the first unit is changed to a closed state from a state where the first unit is not closed, the inclined part abuts on the engagement projection during the change.