Phosphorus (P) is an important element that is applied in the form of di-ammonium phosphate or single super phosphate in potatoes. An experiment was conducted at ICAR-Central Potato Research Station, Patna, Bihar during Rabi, 2017-18 and 2018-19 to evaluate invariably use of phosphorus fertilizers in potato crop. The use of phosphorus is often applied at higher rate than its uptake from the soil. Therefore, experiment was undertaken with the objective to optimize and utilize soil phosphorus more efficiently. Potato variety Kufri Khyati was planted in three replications with eight different treatments of fertilizer phosphorus. Data on tuber yield (t/ha) and tuber number (lacs/ha) was recorded. The maximum tubers were recorded at 20% of recommended dose of phosphorus i.e. 5.14 lacs/ha followed by 100% recommended dose of phosphorus (4.56 lacs/ha). The tuber yield was maximum at 100% recommended dose of phosphorus (33.53 t/ha) followed by 50% recommended dose of phosphorus (31.35 t/ha), which was at par with the yield obtained at 20% (30.29 t/ha) to 40% (29.98 t/ha) of recommended dose of phosphorus. The recorded results showed that the omission of phosphorus does not have any significant reduction in the yield as compare to tuber numbers. Therefore it may be recommended that in high P soils, the maintenance dose of 20 % of recommended dose of P is sufficient to harvest economic yield.