Optical-neural stimulation, which encompasses cutting-edge techniques such as optogenetics and infrared neurostimulation, employs distinct mechanisms to modulate brain function and behavior. These advanced neuromodulation techniques offer accurate manipulation of targeted areas, even selectively modulating specific neurons, in the brain. This makes it possible to investigate the cause-and-effect connections between neural activity and behavior, allowing for a better comprehension of the intricate brain dynamics towards complex environments. Non-human primates serve as an essential animal model for investigating these complex functions in brain research, bridging the gap between the basic research and clinical applications. One of the earliest optical studies utilizing optogenetic neuromodulation in monkeys was conducted in 2009. Since then, the optical-neural stimulations have been effectively applied in non-human primates. This review summarises recent research that employed optogenetics or infrared neurostimulation techniques to regulate brain function and behavior in non-human primates. The current state of optical-neural stimulations discussed here demonstrates their efficacy in advancing the understanding of brain systems. Nevertheless, there are still challenges that need to be addressed before they can fully achieve their potential.