The commercial pilot production and analysis on replacing partial lime in slag by limestone in 60t BOF steelmaking at Tangsteel have been carried out. Results show that of heats with limestone replacement ratio 7%~33% the energy consumption saving is 1.45~6.90kg standard coal per ton steel by estimated calculation；with replacing partial lime by limestone the average end [P] is 0.02% and average dephosphorization rate is up to 83.13%；with tapping liquid temperature increasing the dephosphorization rate in heats replacing partial lime by limestone decreases that meets the law of thermodynamics；and compared with CaO charging amount 51.99kg per ton steel of heats by lime slagging

the CaO charging amount is 51.67kg per ton steel slagging by limestone to replace partial lime which shows no-obvious silicon volatile phenomenon.