An ethnobotanical comparison is made between the four Indian tribes the Denís, the Jamamadis, the Makús, and the Waikás. The data was collected during general plant collecting expeditions in the tribal areas, and is not presented as a complete ethnobotanical study of each tribe. It is a comparison of the botanical data which we were able to gather during short visits to each tribe. A table is given comparing the cultivated crops of each tribe. The following types of plant uses are discussed and compared: fish poisons, arrow poisons, other poisons, narcotic and hallucinogenic snuffs, coca, medicines, contraceptives, edible fruit and fungi and a few other miscellaneous plant uses. Information on the edible fungi eaten by the Waikás is presented for the first time. Various tables are given comparing the different plant uses by the four tribes. Reference is made to past observations and studies of the plants mentioned. Common to all four tribes are several of the most important food crops, fish poisons, some form of narcotic, arrow poisons, and various general uses of plants such as for building materials and body paints. Each tribe has a slightly different narcotic, the Jamamadís and Denís are most similar in this respect having a tobacco based snuff, the Waikás have several hallucinogenic snuffs and the Makú narcotic is coca which is eaten to remove hunger pains. The arrow poisons are also different from tribe to tribe. The Jamamadis and Denís have a Strychnos based curare, the Waikás a Virola, based poison, and the Makús a Moraceae based poison in which cardiac glycosides are present. The Jamamadís and Denís are ethnobotanically the most similar of the tribes compared and they are very different from both the Waikás and the Makús.