The invention discloses an observation method of a Ti-Ni alloy metallographic structure, comprising the following five steps: 1. machining a metallographic observation plane; 2. grinding; 3. mechanically polishing; 4. etching; and 5. observing. The surface of a mechanically-polished sample is etched by an etchant solution, avoids forming an oxidation film as the paraboloid is oxidized, and avoidsgenerating a pseudo structure because of etching. The observation method in the invention is easy to operate, in non-hazardous, can clearly show the Ti-Ni alloy metallographic structure and does not need any special equipment.