. Sumarni, N, Rosliani, R, Basuki, RS, and Hilman, Y 2012. Response of Shallots Plant to Phosphat Fertilization on Several Soil Fertility Levels (Soil-P Status). To achieve an optimum yield, fertilization should be applied based on plant nutrient requirement and soil nutrient content. This experiment was carried out at Screenhouse of Indonesian Vegetable Research Institute from May to December 2008, to find out the optimum dosage of P fertilizer for two shallots varieties on several soil fertility levels (soil-P status). A split-split plot design with three replications was set up for this experiment. Main plots were shallots varieties i.e.: Bangkok and Kuning. Subplots were three soil-P statuses i.e.: low (<15 ppm P2O5), medium (16–25 ppm P2O5), and high (>26 ppm P2O5). Sub-subplots were five levels of P fertilizer dosage of 0, 60, 120, 180, and 240 kg/ha P2O5. Nitrogen fertilizer of 150 kg/ha and K fertilizer (K2O) of 150 kg/ha were applied to all. The results showed that there were interaction effect among varieties, soil-P status, and P fertilizer dosages influencing leaf area, fresh, and dry weight of bulb yield, and P uptake by shallots plant. The optimal dosage of P fertilizer for Bangkok and Kuning varieties on low and medium of soil-P status was still unknown yet, since the relation response curve of relationship between P fertilizer dosages and dry bulb yield was still linear. Meanwhile, in high of soil-P status, the response curve was quadratic for both Bangkok and Kuning varieties. The maximum dry bulb yield was obtained by 126.50 kg/ha P2O5 for Bangkok and 0 kg/ha P2O5 for Kuning. The higher of P fertilizer dosage applied, the higher of residual of P fertilizer detected in soil. The optimum dosage of P fertilizer for shallots production was different depend on variety and soil-P status.