To understand the phylogenetic relationships of Menyanthes and address the existing gap in the evolutionary study of embryological characteristics, we investigated and compared these characteristics with those of related taxa. Our objective was to deduce the evolutionary polarity of these characteristics. We analyzed the dicotyledonous type of anther wall, the development of an endothelium, and endosperm formation of the ab initio Cellular type. Our findings revealed that vascular bundles extending into the integument are an autapomorphy. When compared with the closely related taxon Nymphoides, Menyanthes share common embryological characteristics at the family level, except for three-celled pollen at shedding time. Primitive angiosperm Amborella exhibited tetra-sporangia, glandular tapetum, and other symplesiomorphic characters, while Menyanthes showed apomorphic characteristics such as simultaneous cytokinesis and endothelium development. Although previously classified as Campanulas, embryological characteristics of Menyanthaceae support its reclassification to Asterales in APG system IV. These findings indicate that Menyanthaceae is more primitive than Calyceraceae, Goodeniaceae, and Asteraceae within Asterales. Our study strongly supports the APG system IV classification based on both embryological and DNA data, providing new insights into the evolutionary history of Menyanthaceae