Consideration of the problem of taxonomic diversity as a fractal object is the aim of this paper. The prerequisites for such an approach were the articles with varying degrees of detail and argumentation, which substantiate taxonomic diversity from the standpoint of fractal geometry. Common to these papers is that the authors in their theoretical constructions start from the Willis rule (law) describing the rank distribution of the relationship between the number of taxa and their volume. Flora of the Samara Bend (the bend of the Volga river in its middle reaches) has become an object of the research. We distinguish seven basic floristic areas on the Samara Bend, which boundaries coincide with the respective landscapes. We discuss the efficiency of the Willis rule (law), which approximates the relationship between the number of taxa and their volume by rank distribution. The multifractal spectrum (generalized geometric image of generic structure) of taxonomic diversity of vascular plants of the Samara Bend is presented.Авторы благодарны Российскому фонду фундаментальных исследований (РФФИ), частично поддержавшему данное исследование (грант 17-44-630113 р_поволжье_а)