The heat exchanger is a device that exchanges heat between two flow lines. The goal of this article is to emphasize and presents briefly the heat exchanger designs used for liquefaction of nitrogen gas and subcooling of liquefied gas. Different researchers proposed various heat exchanger designs for liquefaction and subcooling of liquid nitrogen. Liquefied nitrogen gas has many applications. In this article, the heat exchanger designs developed by researchers over time for effective subcooling of liquid nitrogen are addressed and studied. Further content is focused on increasing the effectiveness of this type of heat exchanger for effective subcooling. The gaps in research identified and mentioned in the article.