This article reviewed the moments of the author spending with Professor WANG Yunhua as a supervisor and a pioneer in studying trace element for crops in China based on the 7-year academic learning and studies from undergraduate to postgraduate at Huazhong Agricultural University.The outstanding contributions of Professor WANG Yunhua on promoting researches and application of trace element fertilizers in China were elaborated.There will be no guarantee for food security without trace-element fertilizer. Professor WANG Yunhua has developed a technical system for applying boron in cotton， and molybdenum in winter wheat in China.He has established the Trace Element Research Center and the Department of Plant Nutrition Genetics at Huazhong Agricultural University， and trained a group of senior talents in the field of micronutrient fertilizer.Many of them have become the backbone of education， research， management， production， and administration of plant nutrition in China.Professor WANG Yunhua took boron and molybdenum as the starting point， connecting the national sentiment and mission with trace element fertilizers.Professor WANG Yunhua has played a crucial role in the sustainable development of modern agriculture in China and will always be learned and memorized by the followers.