Although peas cv. master pea was registered more than 25 years ago in Egypt, this variety showed a remarkable superiority over the varieties grown in all governorates of Egypt in terms of production, quality, and environmental adaptation to climate changes. This study intends to assess this cultivar's genetic and environmental traits, and to determine the degree of its deterioration over time to develop an appropriate plan for the maintenance, improvement, and conservation of this strategic variety to withstand changes in climatic conditions in Egypt. Many types of research have been conducted on the study and production of new varieties and lines of peas in Egypt; yet there is a dearth of multivariate analysis as a technique that can combine all variances for all examined qualities using statistics that rely on the algebra of matrices and extract statistical markers from which the researcher can make an appropriate selection program within cultivars without causing genetic erosion. The present experiment was conducted to achieve the following objectives: to monitor the performance of growth traits in the Master pea cultivar using multivariate analysis and UPOV descriptor; evaluation of yield characteristics, seed yield, and quality of Master pea cultivar using multivariate analysis and UPOV descriptor. In this study, one of the most important results obtained was that the phenotypic diversity within the population (measured using the UPOV descriptor) is an important aspect that reflects genetic diversity and the ability of this genetic diversity to withstand changes in the environment. Natural selection - over the many years of the inherited varieties of countries and societies - affects the diversity of phenotypic traits among the individuals of the population. It can be concluded from this study that the phenotypic traits identified in the UPOV descriptor and data analysis using multivariate analysis can show differences between lines within cultivars. Therefore, we recommend taking advantage of the UPOV descriptor and multivariate analysis as a successful way to obtain differences and relationships between lines in conservation, maintenance, and improvement programs for ancient and promising cultivars in the Arab Republic of Egypt.