A thermal printer includes a thermal head, a platen roller configured to press the thermal head, an engaging part configured to engage the platen roller provided at a side part of a main part where the thermal head is provided, and a spring part provided at a part of the side part so as to engage the platen roller with the engaging part. The spring part forms a part of a side surface of the engaging part. The spring part is made of a material the same as a material of the side part.