The objectives were to analyze the competitiveness of countries exporting fruit juices into Japan and simulate the effect of the negative Japanese population growth rate on fruit juice demand. The relative price version of the Rotterdam demand model was estimated for orange, grapefruit, other citrus, apple, pineapple and grape juices. Results indicate that most exporters can’t increase market share through price reductions. Product promotion and product differentiation is a more plausible option. The growth of fruit juice demand in Japan is expected to decrease over the period 2006 through 2020 for 11 of the 18 fruit juice/country combinations because of negative population growth rate.