The novel coronavirus (SARS-CoV-2) caused the COVID-19 pandemic, which led to a large number of deaths worldwide, particularly in rich and developed countries, thereby decreasing the average life expectancy (ALE) or average lifespan (ALS) of the people living in these countries. We investigated the pandemic’s effect on the ALE of the Japanese male and female population. Japan’s declining ALE year-over-year was compared with high-ranking LE countries. For both genders, Japan’s ALE increased every year until 2020, even though 2020 was a pandemic year. A small decrease due to the pandemic could not reduce Japan’s overall LE in 2020. In 2021 and 2022, Japan’s overall LE decreased, but once the pandemic ended in 2023, it returned to its pre pandemic trend of increasing. When considering both genders among the high LE and rich and democratic countries such as Hong Kong, Switzerland, Singapore, Sweden, Norway, Italy, South Korea, and Spain, Japan’s ALE was least affected. Due to its improved health infrastructure (% GDP spending on healthcare) and public awareness about the pandemic (mask usage), Japan remained the least affected country during the COVID-19 pandemic. This paper compares the ALE change, % GDP spending on healthcare, and mask usage awareness of the above countries with Japan.