Objective To investigate the end-digit preference and related factors in blood pressure measurement among inpatients.Methods A cross-sectional study was conducted on the end digits of blood pressure measurement during the admission of patients in a tertiary general hospital of shanghai in 2010,and the related factors were analyzed with the logistic regression.Results The average blood pressure in records of 2276 patients was (125 ± 14) mm Hg(1 mm Hg =0.133 kPa) in systolic and (77 ±9) mm Hg in diastolic.End-digital zero preference accounted for 1874 records (82.3%) of systolic and 1859 records (81.7%) of diastolic readings,which were significant different to the expected frequency of 20% (P < 0.001).Logistic analysis showed that admission of patients not in winter (OR =1.270,OR =1.270),patients in surgical department (OR =1.619,OR =2.045),patients with no history of hypertension (OR =1.432,OR =1.310)were the risk factors of end-digital zero preference in systolic and diastolic pressure measurement.Non-elderly patients (OR =1.288) and patients with normal heart rate(OR =1.823) were related to zero preference diastolic pressure measurement.Conclusions Blood pressure measurement of inpatient displays marked zero end-digit preference.Doctors tend to end in zero when taking blood pressure in some special types of patients.