This study was conducted to provide information on the morphological characteristics and anatomical structures of species belonging to the genus Ludwigia, serving as a scientific basis for the taxonomical classification of this genus for more effective exploitation and utilization of plant resources in Can Tho City. In this study, plant samples were collected, morphological characteristics were described, anatomical structures were examined, and specimens were prepared for observation and photography under an optical microscope. The results showed that L. adscendens differs from other species in the genus Ludwigia by having a stem with spongy roots, white flowers, and abundant spongy parenchyma in the anatomical structure of its stem and leaves. The remaining four species are distinguished by the morphological characteristics of the stem (angled, branched, with or without trichomes), leaves (shape, presence or absence of trichomes), flowers (shape of petals and sepals, number of stamens), and fruit (shape, presence or absence of angles, color). Anatomically, the species can be differentiated by the shape of the stem and fruit cross-sections, while the tissue structure and arrangement in the stem and leaves are quite similar.