The presentation starts as the discussion of the solid-state laser technology, especially the ultrafast and high power laser systems, covering the topics, e.g. the cavity mode phase-locking, chirp-pulse amplification scheme, laser architecture and components etc. It will also address the application of the high power laser for the plasma science towards the thermonuclear inertial confinement fusion (ICF). The general laser-plasma diagnostics, e.g. X-ray spectroscopy and time-resolved measurement will be discussed as well. Especially the development of a self-made state-of-the-art ultrafast X-ray spectrometer prototype will be introduced. The second part of the presentation will discuss about the X-ray free electron laser (FEL) technology, and will present some results from the frontier research and machine commissioning campaigns at the world most advanced FEL light sources (e.g. FLASH and LCLS). Finally the ultrafast laser application for energy materials’ spectroscopy and electron charge transfer dynamics will be briefly discussed.