A seal inspecting machine for inspecting bagged products to determine the presence or absence of a seal abnormality in each bagged product being transported by a transport conveyor 2 includes a presser unit 3 and a servo motor 32 for driving the presser unit 3 to sandwich the bagged product G between the presser unit 3 transport conveyor 2. The servo motor 32 itself has a capability of detecting a reactive force acting on the presser unit 3 or a displacement of the presser unit 3 that occurs as a result of contact with the bagged product, where any failure of the bagged product to exert a sufficient reactive force or displacement resistance is considered evidence of a seal abnormality being present in such bagged product. With this seal inspecting machine, seal check of the bagged products can be efficiently and inexpensively carried out.