BCI stands for Brain-Computer Interface, a technology enabling direct communication between the brain and an external device. The development of BCI has made it possible for the brain and external equipment to communicate directly. An area of BCI that has attracted a lot of attention is ‘Attention Detection’, which includes spotting changes in the brain's electrical activity patterns while someone is paying attention to a particular task. Identification of attentional states with BCI technology has important ramifications in industries including medicine, education, and entertainment. Attentional processes are crucial in a variety of cognitive functions, such as perception, memory, and learning. An in-depth examination of attention detection utilizing BCI technology is provided in this review paper, which also highlights the state-of-the-art techniques and potential future research areas. The report will aid specialists in the field to better comprehend the benefits and drawbacks of BCI -based attention detection systems as well as chances for more study and development.