Abstract: On October 3rd, 2017, one male patient, aged 27 years, was admitted to our hospital 6 hours after hydrothermal scald of torso, buttocks, and limbs. The total area of burn was about 60% total body surface area, and the depth was from deep partial-thickness burn to full-thickness burn. Immediately after admission, the patient was given symptomatic support treatments, such as anti-shock, fluid replacement, and anti-infection, etc. After being treated by debridement and xenogenic (porcine) skin grafting for 2 times, the wounds were healed well. On the 12th day of admission, linezolid was used to prevent infection according to the results of microbial culture and drug sensitivity test, since when the level of his blood lactate continued to increase. After 8 days, linezolid was discontinued and vitamin B1 was given orally for 1 week, and the level of lactic acid gradually decreased to normal in result. This case was used mainly to analyze whether linezolid could directly cause hyperlacticemia and its important mechanism, aiming at reminding clinicians of being alert to the risk of hyperlacticemia when using linezolid. If hyperlacticemia occurs, linezolid should be discontinued immediately and vitamin B1 should be taken orally to correct the high lactic acid value, and the treatment plan should be adjusted if necessary.