Abstract: Dynamic study on the growth and development of virus-free potato variety ‘Quanyun No.4’ were conducted in summer multiplication in Quanzhou high altitude areas. The results showed that the dynamic changes of leaf area, stem and leaf fresh weight, and leaf number were in accordance with the single peak curve. The growth rate of stem and leaf was fast at the early stage of growth, and the peak appeared at 35 days after emergence. The flowering began at the stage of tuber enlargement, and the tuber weight increased rapidly in flowering stage, which was the key period for yield formation. Therefore the high-quality multiplication technique of ‘promote at the first, control in the middle, and defense in the last stage’ was proposed.