Abstract: In every century, few invisible infectious diseases create an alarm to the entire world and which leads to extermination of the population. In 1918 and 2019, the world has tackled truculent diseases such as mother of all pandemic Spanish flu and COVID 19. The mortality rate of Spanish flu was greater than in the first world war. After 100 years’ same history was repeated in 2019 through COVID 19. Suddenly a huge number of pneumonia cases were reported in the end of 2019 in Wuhan, China. These two outbreaks make medical, social and financial burden to the entire world. This kind of sudden pandemic breaks mental health and creates panic, anxiety and depression. Pharmaceutical preventive measures are not supported during both pandemics which was rectified by nonpharmaceutical preventive steps like lockdown, quarantine, wearing facemask and gloves, washing hands and applying sanitizer, follow the social distancing, closing cinema hall and schools, avoiding mass gathering in 1918and 2019-2020. The main objective of this review is to compare and summarize the concepts of both pandemics and how the people of the world need to come together and fight against common enemies, to warrant that we have the best scientific resources necessary to bring this outbreak to an end.