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<i>Pseudoroegneria</i> species play an important role among <i>Triticeae</i> grasses, as they are the putative donors of the St genome in many polyploid species. Satellite repeats are widely used as a reliable tool for tracking evolutionary changes because they are distributed throughout the genomes of plants. The aim of our work is to perform a comparative characterization of the repeatomes of the closely related species <i>Ps. libanotica</i> and <i>Ps. tauri</i>, and <i>Ps. spicata</i> was also included in the analysis. The overall repeatome structures of <i>Ps. libanotica</i>, <i>Ps. tauri</i>, and <i>Ps. spicata</i> were similar, with some individual peculiarities observed in the abundance of the <i>SIRE</i> (Ty1/<i>Copia</i>) retrotransposons, <i>Mutator</i> and <i>Harbinger</i> transposons, and satellites. Nine new satellite repeats that have been identified from the whole-genome sequences of <i>Ps. spicata</i> and <i>Ps. tauri</i>, as well as the CL244 repeat that was previously found in <i>Aegilops crassa</i>, were localized to the chromosomes of <i>Ps. libanotica</i> and <i>Ps. tauri</i>. Four satellite repeats (CL69, CL101, CL119, CL244) demonstrated terminal and/or distal localization, while six repeats (CL82, CL89, CL168, CL185, CL192, CL207) were pericentromeric. Based on the obtained results, it can be assumed that <i>Ps. libanotica</i> and <i>Ps. tauri</i> are closely related species, although they have individual peculiarities in their repeatome structures and patterns of satellite repeat localization on chromosomes. The evolutionary fate of the identified satellite repeats and their related sequences, as well as their distribution on the chromosomes of <i>Triticeae</i> species, are discussed. The newly developed St genome chromosome markers developed in the present research can be useful in population studies of <i>Ps. libanotica</i> and <i>Ps. tauri</i>; auto- and allopolyploids that contain the St genome, such as <i>Thinopyrum</i>, <i>Elymus</i>, <i>Kengyilia</i>, and <i>Roegneria</i>; and wide hybrids between wheat and related wild species.