ObjectiveTo investigate the effect of maximal sterile barrier precaution during deep venous/arterial catheterization on preventing catheterrelated bloodstream infection (CRBSI) in patients in the department of critical care medicine. Methods996 patients who were hospitalized in Beijing Friendship Hospital and underwent deep venous/arterial catheterization from September 2011 to April 2014 were analyzed retrospectively, patients were divided into standard sterile barrier precaution group (SSB group, September 2011December 2012, n=560) and maximal sterile barrier precaution group (MSB group, January 2013April 2014, n=436) based on whether they received maximal sterile barrier precaution, incidence of CRBSI and mortality were compared between two groups. ResultsThere was no statistical difference in constitute of intubation sites between patients in SSB group and MSB group（χ2=6.750，P=0.08）. The incidence of CRBSI per 1 000 catheter days in SSB group and MSB group were 2.41‰（1.64‰-4.02‰）and 1.91‰（0‰-4.56‰）respectively，rank test revealed no significant difference（Z=-0.057，P>0.05）；24 （4.29%）patients in SSB group and 26（5.96%） patients in MSB group developed CRBSI, difference between two groups was not statistically significant（χ2=1.447，P>0.05）. The mortality in SSB group and MSB group were （18.43±5.53）% and （11.68±4.14）% respectively，independent sample ttest revealed that difference was significant（t=3.907，P<0.05）. ConclusionMaximal sterile barrier precaution did not reduce the incidence of CRBSI.