Background. Frailty was believed to reflect patients' prognosis better than age, but studies regarding the association between these factors are controversial. Moreover, studies highlighting the association of gender to mortality risk in frail patients are limited. Objectives. We aimed to investigate the association of frailty to mortality risk with the dose-response relationship of CFS and the association of gender to mortality risk in frail elderly with COVID-19. Material and methods. We performed a comprehensive literature search from several databases, such as europePMC, PubMed and DOAJ on 9 July 2021. We searched for studies investigating the association between frailty and mortality in COVID-19 patient. Results. A total of 16,438 patients from 15 studies were included. Frailty was found in 52.67% of the patients. the lowest mean age was 65.4 ± 15.8 years. Pre-frailty (OR 2.07 [1.53-2.79]; p < 0.00001; I 2 : 72%), mild frailty ; p = 0.00001; I 2 : 80%), moderate frailty ; p < 0.00001; I 2 : 79%) and severe frailty ; p < 0.00001; I 2 : 83%) increase the mortality risk in elderly with COVID-19. Each 1-point increase in CFS increases the mortality risk by 1.4 [1.3-1.5]; p = 0.000; I 2 : 98.6%. Men had a lower risk of frailty ; p = 0.0004; I 2 =36%) but higher mortality risk. Conclusions. This meta-analysis showed that pre-frailty and frailty increase the mortality risk in elderly with COVID-19. Each 1-point increase in CFS increased the mortality risk by 1.4. Men had a lower risk of frailty but higher mortality risk.