In this review, we describe experimental studies on structures and dynamics of molecules on clean liquid surfaces in a vacuum. These studies use clean-surface preparations in combination with highly sensitive laser-, photoelectron-, and mass-spectroscopic techniques. In particular, we refer to our recent studies on solvation structures and reactions on various solution surfaces using liquid beam-multiphoton ionization-mass spectrometry. These include (a) aggregation of solute molecules on solution surfaces such as formation of solute pairs, clusters, and islands; and (b) chemical reactions induced by photoexcitation and -ionization, such as a nucleophilic reaction of phenyl ketones, polymerization of halo-anilines, and reduction of cations by solvated electrons.