<p>Gallium (Ga)-based liquid metals (LMs) have attracted considerable interest in the scientific community because of their remarkable properties. Among their most notable characteristics are high surface tension, density anomalies, and outstanding electrical and thermal conductivity. Additionally, these LMs demonstrate distinctive rheological behavior. In their oxide-free state, Ga-based LMs behave as Newtonian fluids with a low viscosity comparable to that of water. However, Ga rapidly and almost immediately oxidizes when exposed to ambient atmospheric conditions, forming an oxide layer on its surface. This oxide layer imparts considerable elasticity and yield stress to the LM. In this review, we provide a summary of the literature on the viscoelastic properties of Ga-based LMs, in the presence and absence of the surface oxide layer. Furthermore, the viscoelasticity of the oxide layer has been used in a range of applications, including soft electronics, 3D printing, and microfluidic device components. Therefore, we also highlight several examples that illustrate how these viscoelastic properties can be leveraged for practical applications.</p> Graphical Abstract <p></p>