Nils Wallerius (Stora Mellösa 1 January 1706 – Funbo 16 August 1764) was a Swedish physicist, philosopher and theologian. He was one of the first scientists to study and document the characteristics of evaporation through modern science methods and also one of the first and most important followers of Christian Wolff in Sweden.Nils Wallerius was born as the son of provost Erik Nilsson Wallerius of Stora Mellösa and his spouse Elisabeth Tranæa.