The COVID-19 pandemic brought about drastic changes all across the world, causing the loss of thousands of lives and negatively affecting many industries, owing to the health measures taken by authorities in this period. The difficulties engendered by the pandemic have led to excessive anxiety and made people vulnerable to psychological problems. Moreover, many people have lost their jobs or experienced anxiety of losing their jobs. Turkish business is one of the prominent markets that have been severely affected by the pandemic. Thus, we considered it crucial to examine how life satisfaction levels of individuals working in the Turkish business sector can be increased through psychological capital. We also aimed to test whether a sense of job security has a mediator effect in the relationship between life satisfaction and psychological capital. In order to test the assumed relationship, we collected data from Turkish professionals working in the Marmara region. The collected data were analyzed using SPSS AMOS and the results revealed that psychological capital has a positive effect on life satisfaction levels of individuals. Moreover, our study is novel in that it revealed the mediator role of job security in the relationship between psychological capital and life satisfaction.