The invention provides a tire pressing device and a tire forming machine. The tire pressing device comprises a support, air cylinders, swing arms and a compression roller mechanism. The air cylinders and the swing arms are connected to the support in a rotating mode. The ends of piston rods of the air cylinders are hinged to the swing arms. The compression roller mechanism comprises an installation supporting plate, a pressing machine head and a first driving mechanism used for driving the pressing machine head to slide in a reciprocating mode. The pressing machine head comprises a mounting rack, a first rotary arm, a second rotary arm and a second driving mechanism used for driving the first rotary arm and the second rotary arm to rotate synchronously in opposite directions. Compression roller assemblies are arranged at the free end of the first rotary arm and the free end of the second rotary arm. Each compression roller assembly comprises compression rollers, guide shaft sleeves, compression springs and a mounting shaft. The corresponding guide shaft sleeves are connected to each mounting shaft in a sliding mode in the direction perpendicular to the axis of the mounting shaft. The compression springs are arranged between the guide shaft sleeves and the mounting shafts. The compression rollers are connected to the guide shaft sleeves in a rotating mode. By the adoption of the tire pressing device, the pressing quality of tires and the production efficiency are improved.