The present invention provides a pharmaceutical complex formulation comprising a first mixture including amlodipine and chlorthalidone and a second mixture including losartan, which has an improved dissolution and stability. The complex formulation according to the present invention may achieve improved preventive or therapeutic effects for cardiovascular diseases by actuating different mechanism of amlodipine, losartan and chlorthalidone, and exhibits high dissolution rates of amlodipine, losartan and chlorthalidone and improved storage stability, due to the minimized drug interactions, and therefore, it is useful in the fields of pharmaceuticals and medicine.