Agriculture is the backbone of human survival and economic stability since the beginning of time. In developing countries like Nigeria, Agriculture provides food security, generates several employment opportunities for the nation's populace. Agricultural produce is essential in feeding the increasingnation’s population. Although, agricultural produce faces challenges such as inadequate storage facilities which leads to post-harvest losses, poor transportation networks, high input costs etc. One of the major solutions to these challenges is by enhancing post-harvest management through effective agricultural extension services. Good post-harvest management helps in reducing losses, maintain produce/product quality, thereby extending shelf life. This paper highlights post-harvest losses in Nigeria's agriculture, the importance of effective extension services in reduction of post-harvest losses, the current challenges facing Nigeria's post-harvest produce, proposed solutions to address the problems, case studies and examples of several post-harvest losses in Nigeria. It was concluded that enhancement of post-harvest losses through effective extension services could beneficial to Nigeria's economy and enhance its populace livelihood, ensuring enough food supply all year round. It was also recommended that government should invest in post - harvest enhancement by creating farmer awareness programs, provision of innovative storage facilities to farmers, strengthening extension services etc. Individuals in turn should also try and adapt to new technologies and implement them in order to ensure the nation's food security.