The article is devoted to analysing bestiary images in the dilogy “Lulu” by the German dramatist Frank Wedekind (1864-1918). The study focuses not on the traditional mythological interpretation of certain images but on their interrelation with F. Nietzsche’s philosophical conceptions. Specificity of the “beast” notion and peculiarities of the opposition “beast - human being” in Wedekind’s creative work are revealed. Within the framework of the research, the paper examines the motive of animal training, which is a key one in Wedekind’s creative work. Relying on the findings, the researcher suggests deeper interpretation of the “Lulu” dilogy taking into account specificity of the author’s conceptions.