ABSTRACT Ornamental plants are cultivated for decorative and utility purposes in urban landscapes throughout the world. They are much valued for their aesthetic properties and constitute an important part of the global horticulture industry. Plant viruses and viroids of various taxonomic groups have a significant negative impact on ornamentals provoking a wide range of symptoms, reducing both decorative value and quality of propagated material and causing large economic damage. A significant growth of the ornamental plants market in recent years promotes the spread of viral diseases. Therefore, systematization of data on virus and viroid phytopathogens diversity in these cultures is an urgent research task. Among the most popular ornamentals are chrysanthemum, rose, clematis, canna, and lavender. More than fifty viruses and viroids from 17 different families (including two viroid families) have been identified in these crops to date. In the presented review, we described the variety of these pathogens and their effect on the above-mentioned ornamentals.