Growth and chlorophyll fluorescence responses of Spondias purpurea plants to salinity were studied under greenhouse conditions to evaluate the salt tolerance of this species. Plants were irrigated with rainwater (control), or with a 1-, 2-, 4- or 8-dS m-1 solution of sea salt for a period of 15 weeks. Complete defoliation and partial shoot tip die-back occurred on plants receiving 8 dS m-1, and partial defoliation occurred on some plants receiving 4 dS m-1. Chlorophyll fluorescence was measured on dark-adapted leaves, and results indicated that salinity caused a reduction in photochemical efficiency. Leaf area, dry weight, and trunk area were severely reduced by all levels of salinity. Shoot length was reduced by salinity of 2 dS m-1 or higher. These results indicate that S. purpurea is highly sensitive to salt stress and that chlorophyll fluorescence may be a useful tool for further evaluation of the responses of this species to salinity.