Abstract: Objective In this paper,a new algorithm is given for computing the smallest-area enclosing rectangle ofpoints,lines and polygons.First,the problem of calculating the smallest-area enclosing rectangle for points,lines and polygons is converted to the problem of computing the smallest-area enclosing rectangle for theirconvex hull.Secondly,the four points of the rectangle for a convex hull are computed by geometric computa-tion.The computation of many angles of rotation and coordinate transformations is avoided in order toimprove the precision.Finally,the new algorithm is verified with some examples.