This paper presents a step-by-step approach in statistical and genetic analysis applied in diallel mating design using Griffing’s experimental Method II, Model II. A two-step approach is developed and implemented in order to assist the researchers in statistical and genetic analysis of diallel crossing using Griffing’s experimental Method II, Model II. The approach is exemplified on the corolla diameter of Calendula officinalis L. Descriptive and inferential approaches of statistical analysis on experimental data are applied. Statistical analyses describe experimental data and compare means among progenies as well as between the crossover mean and the overall mean. The ANOVA results proved the appropriateness of the ANOVA test for combining ability. Statistically significant differences among progenies were identified. Since the ANOVA statistics identified a statistically significant model, the genetic analysis proved to be appropriate. The genetic analysis was able to identify the appropriate parent(s) needed to obtain plants with larger corolla diameter.