The high mountain ecosystems are characterized by low air temperatures and nocturnal freezing, changing their occurrence with latitude, altitude and topography. The minimum temperature is an important variable in the limits of vegetation distribution, due to the different sensibility and resistance capacity of the species. Thus, tropical and extratropical plants present different strategies to survive, furthermore related with the avoidance and/or tolerance mechanims against freezing. This review attempts to explain the role of low temperatures in the altitudinal limits of higher plants ecosystems, comparing the adaptative responses to low temperatures in tropical and subtropical high mountain species. The higher limit of the forest in tropical mountains in the east of Africa and the north of the Andes correspond with freezing-free altitude, contrasting with Mexico, where this environmental factor sets out the boundaries of mixed and coniferous forests. However, in tropical mountains below the altitude of treeline, the factors that separate differents types of vegetation depend not only on the temperature. In contrast, in the temperate mountain regions of Northamerica, dominated by evergreen coniferous forests, the capacity of supercooling under low temperatures has been described as the explanation for the treeline formation and the altitudinal distribution of tree species. On the other hand, the latitudinal patterns of forest in the high mountain in the east and south of Asia suggest that the altitudinal zonation is related to seasonal temperature fluctuations, deferring from the north and south of 20 degrees N. in Japan. which has subtropical to severe cold climates from south to north, the temperature has been indicated as the determinant factor of vegetation zones. In the South Hemisphere, with mild seasonal changes, the altitudinal distribution of trees in forests of evergreen and coniferous species, are related with their resistance to Freezing. In these temperate zones, plant species have a transitional period from low to high level of resistance against low temperatures and freezing: this cold acclimation allows these species to face the climate of subtropical latitudes. In tropical high mountain species in the Andes, Hawaii and Africa. low temperatures avoidance by supercooling and the freezing tolerance mechamisms would be related. besides. with the plant life-forms: plants that grow at the soil level show tolerance, the shrubby ones avoidance and the intermediate stratum exhibits both mechanisms. This pattern between plant lift-form and low temperature resistance mechanism, also described for subtropical Andes in Chile, would be related to microclimatic conditions around the species. Finally, the effect of freezing temperatures in higher plants seems to be a major factor, but not the only one, that limits the latitudinal and altitudinal distribution of species.