Advancements in genome-wide association studies (GWAS) and quantitative trait locus (QTL) mapping have significantly benefited the field of cucumber breeding. These approaches enable the identification of key genetic factors underlying important agronomic traits. QTL mapping has been instrumental in pinpointing genomic regions associated with disease resistance, yield, and fruit quality. For example, the discovery of QTLs linked to resistance against powdery mildew and downy mildew has facilitated the development of more resilient cucumber varieties. Leveraging the genetic diversity present in diverse germplasm collections, GWAS has further identified candidate genes associated with quantitative traits, thereby enhancing our understanding of trait inheritance. Through GWAS, genetic loci related to fruit size, color, and stress tolerance have been successfully mapped. Consequently, cucumber breeding programs have become more efficient, enabling the production of cultivars that align with consumer preferences and adapt to various environmental conditions. The integration of QTL mapping and GWAS has accelerated the development of improved cucumber varieties by providing a robust framework for marker-assisted selection (MAS) and genomic selection. These genomic tools are revolutionizing cucumber breeding, facilitating higher yields, enhanced disease resistance, and superior fruit quality.