This dataset contains the complete experimental data used in the study entitled “Integration of Digital X-ray Imaging and Automated Seedling Phenotyping for Seed Quality Assessment of Maize Landraces”. The dataset includes measurements obtained from 24 maize landraces and one commercial hybrid reference, encompassing: • Seed physical attributes derived from digital X-ray imaging, including morphometric and densitometric descriptors (e.g., seed area, perimeter, circularity, relative density, integrated density, and gray-value-based measurements); • Physiological quality assessments, including germination, first count, emergence, emergence speed index, accelerated aging, moisture content, seed infestation, purity analysis, and thousand-seed weight; • Digital seedling phenotyping variables obtained through automated image analysis, including shoot length, root length, total seedling length, shoot dry mass, root dry mass, and vigor-related indices; • Supporting data used for correlation analysis, multivariate statistics, and principal component analysis (PCA).