Abstract: The rapid advancement of ultra-short and ultra-intense laser technology has established laser-plasma acceleration as a premier approach for generating GeV-level electron beams and high-quality radiation sources. Among these, Betatron radiation—emitted as electrons oscillate transversely in plasma channels—has emerged as a unique source characterized by its femtosecond pulse duration, micron-scale source size, and high peak brightness. It holds significant potential in high-energy-density physics, materials science, and ultrafast imaging. This review systematically outlines the physical principles and reviews the latest research progress of Betatron radiation generated via two core mechanisms: laser wakefield acceleration (LWFA) and direct laser acceleration (DLA). A detailed comparison reveals that while the LWFA scheme excels in producing highly collimated, high-energy photons with superior brilliance, the DLA mechanism within near-critical-density plasmas offers a different trade-off. Although DLA generates a significantly larger number of electrons and a higher photon flux, these are characterized by lower photon energies and a wider angular spread. Consequently, the divergence of the emitted X rays typically reaches hundreds of milliradians, which limits the overall brilliance. The review concludes that the future of Betatron radiation lies in enhancing repetition rates and achieving active control over radiation parameters. Developing hybrid schemes and structured targets offer potential to overcome the trade-off between high flux and high brilliance, guiding future experiments at large-scale facilities.