Orchid seeds of sixteen Brazilian Southern species were stored at 5°C up to 42 months, when the viability was tested by the tetrazolium or germination performance. There was loss of viability when storage was extended. For one year, the viability of the majority of the seeds stored at 5°C in a dessecator with ± 6% of water content was preserved near to 100%, except for Cattleya labiada which lost around 50% of its seeds? viability. Cattleya intermedia, Encyclia pigmaea, E. odorantissima, Grobya sp., Oncidium flexuosum, O. pumilum and one natural hybrid of Laeliocattleya maintained seed viability of over 90% to 24 months at 5°C. Cattleya intermedia seeds were stored in polipropylene tubes at 5°C or -18°C and either 25°C in a dessecator or in open flasks under laboratory environmental conditions. Most the seeds of this species died under laboratory conditions in one year. Storage at 5°C or in a freezer (-18°C) were the best conditions to maintain the orchid seed viability. With this same species the seeds were stored at -18°C for 24 weeks, and the viability tested weekly.. The seeds were transferred directly from this temperature to 25°C or indirectly, for one hour at 5°C, and then to the environmental temperature in the laboratory (25°C). The indirect transfer preserved viability more efficiently.