Study of the pollen morphology of the Palmae by using scanning electron microscopy and transmission electron microscopy shows that there is more remarkable variation and parallelism in pollen characters, especially exine ornamentation and stratification, than has been demonstrated previously. The pollen of Arenga borneensis has gemmate exine ornamentation and closely resembles that of species of the closely related Caryota (Caryoteae) as well as Iriartea and Dictyocaryum (Iriarteae). Some species of Pinanga (Areceae), Korthalsia, and Daemonorops (Calameae) have pollen which can only be separated from the A. borneensis type by careful electron microscope study. Other species of Arenga have spiny pollen with a smooth foot layer, which resemble Wallichia (Caryoteae) and other Caryota species. Catoblastus, Wettinia, and Socratea (Iriarteae) have similar characteristic pollen with columellate spines interspersed with dense scabrate ornamentation. Again, species of Pinanga and Korthalsia have superficially similar pollen, as do the genera Mauritia, Mauritiella, and Lepidocaryum (Lepidocaryeae). However, these groups can be distinguished by structural differences of the spines. Very similar tectate, perforate pollen with supratectal spines occur in genera which have small differences in apertures but are widely separated taxonomically. These include Pinanga, Nypa, Salacca (Calameae), and Ravenea (Ceroxyleae). In view of this variation and parallelism it is suggested that there is a need for caution in assigning fossil pollen to extant genera until a much more detailed and extensive study of palm pollen morphology is carried out.