In the last century, there are major advances on the existence and structure of minimal sets. In 1968, F. Almgren has showed that if a minimal cone over a smooth hypersurface in {\mathbb R}^4 is stable, then the cone must be a hyperplane. In 1975, J.Taylor gave a complete local description of two-dimensional minimal surface in {\mathbb R}^3. Yet the existence of least-area soap films with given boundary in {\mathbb R}^3 and their structure in higher dimensions remains open. In this talk we give some results of regularity of three-dimensional minimal cones in {\mathbb R}^n, we also treat the regularity of three-dimensional minimal sets in some particuliar cases.