Thailand is the home to 178 genera and about 1,300 orchid species which are the major tropical orchids in the world. Many genera, namely Aerides, Ascocentrum, Bulbophyllum, Dendrobium, Paphiopedilum, Phalaenopsis, Rhynchostylis, Spathoglottis, and Vanda are popular for growing and highly contribute to Thai orchid industry for as cut-flower and potted plants. The improvement of the orchids which have outstanding horticultural characteristics is well-developed through breeding with the support of tissue culture, cultural practices, technology application, extension, and further research. Orchids will continue to dominate other ornamental crops in Thailand due to orchid diversity, better technology know-how from research, suitable climatic conditions, experienced and skillful growers, and exporters, as well as their nationwide popularity.