This paper presents two case studies of walnut quality assessment at room temperature storage of 20 ± 20C. The conformity of the Juglans regia L. walnuts, the Calarasi variety, (harvest 2015) and Cogalniceanu variety (harvest 2016) was analyzed by applying the Pareto diagram and nP-card. These methods present a process of risk analysis, involves obtaining, analyzing and modeling information, analyzing and adopting a decision that improves the product quality. The data were collected during storage of walnuts at room temperature 20 ± 2° C for 6 and 12 months, respectively. The external and internal defects of walnuts have been assessed and grouped by risk categories. The most widespread defects of walnuts, which diminish their quality and the weight of their use on an industrial scale have been emphasised. It has been found that temperature and humidity are critical factors when storing walnuts. It is proposed a primary scheme for the in shell walnuts processing.