This study was to investigate the frailty status of inpatients older than 65 years old in Shanghai.A 6-month cross-sectional survey was conducted using FRAIL (fatigue, resistance, ambulation, illness, and loss) questionnaire. Totally 587 patients were included. The data, including demographic characteristics, constipation, urinary retention, urinary incontinence, grip strength, and muscle strength, were collected. The data of serum prealbumin, serum albumin, serum total protein, and hemoglobin were obtained from laboratory blood tests.The incidence of nonfrailty, prefrailty, and frailty was 0.249, 0.417, and 0.334, respectively. The high incidence age of frailty was 86 to 90 years old (0.342), and the high incidence age of prefrailty was 65 to 70 years old (0.282). There was significant difference in the grip strength among different degrees of frailty (P < .01). The influencing factors related to prefrailty included prealbumin, grip strength, urinary retention, constipation and education level of illiterate (P < .05). The populations with high prealbumin level, high grip strength and illiteracy population were not easy to enter the prefrailty period, while those with constipation (OR (odds ratio) = 1.867, 95% CI (confidence interval): 1.046-3.330) and urinary retention (OR = 7.007, 95% CI: 1.137-2.757) were more likely to enter the prefrailty period. Factors associated with frailty included age, prealbumin, grip strength, muscle strength, urinary incontinence, urinary retention, and constipation (P < .05). The populations with high prealbumin level, high grip strength, and high muscle strength were not easy to enter frailty period, while those with older age (OR = 1.141, 95% CI: 1.085-1.200), urinary incontinence (OR = 10.314, 95% CI: 1.950-54.548), urinary retention (OR = 3.058, 95% CI: 1.571-5.952), and constipation (OR = 3.004, 95% CI: 1.540-5.857) were easy to enter frailty period.The high incidence ages of frailty and prefrailty are 86 to 90 years old and 65 to 70 years old, respectively. Age, low education level, low grip strength, low muscle strength, low serum prealbumin, urinary retention, urinary incontinence, and constipation are the risk factors of frailty. It is recommended to include frailty as an indicator in the existing assessment to rate the disease and develop a disease observation plan.