ObjectiveTo evaluate the efficacy and safety of linezolid in the treatment of grampositive coccus infection in the elderly.MethodsClinical data of patients (>60 years old) infected with grampositive coccus and treated with linezolid for 10 days between January  2013 and December 2014 were collected, the therapeutic efficacy of linezolid were analyzed, laboratory indexes before and 14 days after   linezolid treatment were compared, possible adverse effects were analyzed.ResultsA total of 70 old patients were enrolled, the majority of patients were infected in lower respiratory tract (62.86%)  and were infected with Staphylococcus aureus (42.86%, of which 19 were MRSA), more than 80% of the patients were >70 years old, had length of stay > 30 days, and admitted in ICU, more than 70% of the patients were with deep venous catheterization and indwelling urinary catheterization. Platelet count (PLT) after 14 days of linezolid treatment was significantly lower than before treatment（［132.00±45.00］×109/L vs ［156.00±78.00］ ×109/L, P=0.009); the total therapeutic efficacy of linezolid was 81.43%(57/70), while the rate of adverse effects was 17.14% (12/70).ConclusionLinezolid is effective for treatment of grampositive coccus infection in the elderly, and may be a good choice of empirical treatment. PLT should be intensively monitored during the process of linezolid therapy.