Perovskite structure rare-earth nickelate SmNiO3 film has recently aroused wide attention in academia for its good weak electric sense, which is analogous to that of the ampullae of shark. It can be postulated that SmNiO3 could be used in oceanic environments for monitoring electrical signals from maritime vessels and sea creatures. In this paper, the preparation method, advantages and disadvantages of SmNiO3 film are discussed in detail. SmNiO3, this strongly correlated quantum materials has positive Gibbs Free Energy (ΔG). Thus, preparation of SmNiO3 needs hush experimental conditions such as high pressure and temperature. Since Ni3+ is semi-stable at room temperature and atmospheric pressure, the process of Ni3+→Ni2+ is easy to occur. In order to maintain electrical neutrality, oxygen vacancies would appear in the form of compensation. That is the reason most SmNiO3 film prepared by researchers has oxygen deficiency. While oxygen deficiency would lead to larger lattice parameters, and destroy metal-insulator phase transition. Therefore, the preparation of SmNiO3 requires higher temperature and oxygen pressure. The metal-insulator phase change type, mechanism and main factors affecting the TMI of SmNiO3 thin film materials are mainly introduced: most studies consider that the MI phase transition of SmNiO3 film is caused by the strong electron-electron correlation of Mott type, which is actually disordered and electron-electron interactions should exist at the same time. MI phase change should not be considered separately, which is essentially the coulomb interaction in charge carriers at lower temperature. The thermal activated conduction, Mott variable range hopping conduction and Efros-Shklovskii variable range hopping conduction should be considered in a certain temperature range. Under external conditions such as electric field, temperature, light and pressure, SmNiO3 film would undergo a significant metal-insulator phase transition. And finally, a prospect SmNiO3 film in underwater electric field sensors, data storage, modulation swithches, etc.