Abstract: Design pattern is redefined to focus on its quality focus. An approach, based on object-oriented quality model, is provides to validate if a design pattern answers whether a proposed structural model of the design pattern really resolves quality problems described in intent of the design pattern. A validation approach is proposed to check if the design pattern is well-designed. In addition, a quantitative method is proposed to measure an effectiveness of quality improvement of the design pattern for determining whether the design pattern is applicable to meet functional and quality requirements.