The stainless steel tube has an inner diameter of 6.0mm or more and an annealed stainless steel tube with a wall thickness of 13mm or less. It can be a W-B75 type Vickers hardness tester. It is very fast and simple to test and is suitable for rapid and non-destructive inspection of stainless steel pipes. Stainless steel tubes with an inner diameter of more than 30 mm and a wall thickness greater than 1.2 mm are tested with a Rockwell hardness tester to test HRB and HRC hardness. Stainless steel tubes with an inner diameter of more than 30 mm and a wall thickness of less than 1.2 mm are tested with a surface Rockwell hardness tester to test HRT or HRN hardness. For stainless steel pipes with an inner diameter of less than 0 mm and greater than 4.8 mm, the hardness of HR15T is tested by a special Rockwell hardness tester for pipes. When the inner diameter of the stainless steel tube is larger than 26 mm, the hardness of the inner wall of the tube can also be tested by a Rockwell or surface Rockwell hardness tester.