The cell wall of acid resistant Mycobacterium contains a large amount of lipids and is generally not suitable for staining. Fluorescence staining is relative to acid resistant staining. High detection sensitivity can significantly improve the detection rate of low bacterial content specimens. Under a fluorescence microscope, the morphology of acid resistant Mycobacterium labeled with fluorescent signals is clear and visible, and the structure is typical. It can be clearly determined under a 40x microscope, making it easy to observe.