Background: The mortality and severity in COVID-19 is increased in patients with comorbidities. The aim of this study was to evaluate the unknown risk of severity and mortality in COVID-19 patients with underlying kidney and liver diseases. Method: We retrieved data on the clinical features and primary composite end point of COVID-19 patients released from inception till 16th of April 2020 from Medline and Embase. The data on two comorbidities, liver diseases and chronic kidney disease, present in COVID-19 were pooled and statistically analysed to explain the associated severity and mortality rate. Results: 142 abstracts were screened, and 41 full articles were then read. In total, 22 studies including 5595 COVID-19 patients were included in this study with case fatality rate of 16%. The prevalence of liver diseases and CKD were 3% (95%CI; 2%-3%) and 1% (95%CI; 1%-2%) respectively. In patients with COVID-19 and underlying liver diseases, 57.33% (43/75) cases were severe with 17.65% mortality. While in CKD patients with COVID-19, 83.93% (47/56) severity and 53.33% (8/15) mortality were reported. Conclusion: This study found an increased risk of severity and mortality in COVID-19 patients with liver diseases and CKD. This will allow for better clinical management and inform more stringent preventative measures for this group of patients.