The factors governing phytoplankton production in the Indian Seas have been briefly discussed. The general level of productivity of the Exclusive Economic Zone of India has been computed from primary production measurements using radioactive carbon ("Q in different depth zones during different seasons. From this a potential estimate of the harvestable resources has been derived. The annual carbon production for the EEZ of India, comprising 2.02 million sq. km. has been estimated to be 283 million tonnes. The present exploitable yield of living resources of the EEZ is estimated to be 5.5 million tonnes based on primary production. This estimate is about 20% higher than the earlier estimates.