Microscopic image enhancement plays a crucial role in understanding the details of biological cells and materials at the microscopic scale. In recent years, significant progress has been made in microscopic image enhancement, particularly through the use of deep learning methods. This review paper aims to provide a current overview of this rapidly evolving state-of-the-art method, focusing on its evolution, applications, challenges, and future directions. The core discussion focuses on key areas of microscopic image enhancement: super-resolution, reconstruction, and denoising, each of which is explored in terms of current trends and the practical utility of deep learning.