The properties of an aqueous film confined between charged surfaces are extremely important in many fields, such as the colloidal stability in colloid science, clay swelling in geological science, and nanofluidics in many nanoscale channels. Specifically, understanding the hydration force mechanism when aqueous electrolyte solutions are confined between two charged surfaces is critical in the development of highly efficient aqueous lubricants for nanoscale machines and biolubrication in many biological environments. This talk will present some results through molecular dynamics (MD) simulations on the hydration force mechanism when a dense electrolyte droplet is confined between two mica surfaces. Very strong repulsive hydration force has been obtained and was attributed to the overlaps of hydration shells of the hydrated metal ions and co-ions. The fluidity and dynamic squeeze out behavior of the aqueous droplet during normal approach will also be discussed.