NiTi alloys are common shape memory alloys with good shape memory effect superelasticity corrosion resistance and biocompatibility. They have a wide range of applications in biomedical aerospace and microelectromechanical fields. Objective The wetting properties of different nanoscale structures on the surface of NiTi alloys were investigated to improve the wear and tear of NiTi alloys in the working environment and to increase the service life of NiTi alloys. Methods A molecular dynamics approach was used to simulate the shape memory effect of NiTi alloys under periodic boundary conditions to study the microstructural evolution of NiTi alloy atoms at different temperatures. Meanwhile based on the different microstructures of NiTi alloys under the temperature response a droplet static contact angle simulation was built to investigate the wetting properties of NiTi alloy surface under different microstructures. Results NiTi alloys were found to undergo phase transformations in response to different temperatures resulting in changes in the surface atomic arrangement of NiTi alloys. The temperature-induced phase transition and reverse phase transition behaviors of NiTi alloys as well as the microstructural evolution at the atomic scale were demonstrated. The surfaces of NiTi alloys undergoing phase transition and reverse phase transition at different temperature responses were then used as substrates and it was found that the wettability of their surfaces has also changed and recovered. Conclusion NiTi alloy undergoes phase transformation in response to temperature the microstructure changes and its surface wettability also changes NiTi alloy undergoes reverse phase transformation in response to temperature the microstructure is restored to the initial state and its surface wettability can be restored to the initial state accordingly. The austenite and martensite content of NiTi alloys during phase transformation affects the surface wettability of NiTi alloys. Therefore it is possible to adaptively regulate the wettability of NiTi alloy surfaces in the microstructure by temperature.