Objective To improve the dose accuracy of antibiotics commonly used in neonatal intensive care unit (NICU). Methods Fourteen kinds of antibiotics commonly used in NICU were selected, and an antibiotics preparation method （also called specification method） which required addition of a certain volume ［solvent volume=specification(mg)/100 for 13 antibiotics, while 4 mL was added into the penicillin G (specification 80 0000 U) vial］ of 0.9% sodium chloride into the antibiotic vials was used to prepared the IV solutions. Then the actual dose of each antibiotic in the IV solution was calculated, and compared with theorectical dose（the correct dose）.An increase or decrease over 10% from theorectical dose was deemed IV medication error. Results Except for imipenem-cilastatin(12.28% decrease) and erythromycin(11.76% decrease),the other 12 antibiotics had a decrease of 0.79% to 9.09% from theorectical dose. Conclusion For most antibiotics, the specification method of antibiotics can be used to prepared IV fluids for NICU patients, while the preparation of imipenem-cilastatin and erythromycin need to be standardized.