Groundwater is the most abundant freshwater resource available on Earth. It is a source of drinking water for more than 2 billion people, also providing more than 40% of water resources for irrigated agriculture. Land use change accompanied with various human activities is expected to have substantial impact on groundwater quality and contamination at regional scales throughout the twenty-first century, especially in urbanized areas. For example, the wholesale transformation of agricultural and natural ecosystems to more intensive uses of urbanization and industrialization has a strong negative impact on groundwater quality worldwide. As a consequence, in order to enhance the utility of groundwater resources under the condition of land use change, knowledge on the status of groundwater quality and contamination at regional scales is required. Therefore, this reprint presents a vast array of information on regional groundwater quality and contamination in several countries such as China, India, Uganda, and Ethiopia. In addition, a systematic review on advanced analytical approaches for phenolic compounds in groundwater was also included. We hope that it will be a useful reference for related readers, hydrogeologists, and departments of water resources' development and utilization.