Abstract The objective of this research is to study the selected inorganic materials and organic molecules using laser ablation/laser desorption ionization (LA/LDI), or matrix-assisted/surface-assisted laser desorption ionization (MALDI/SALDI) with time-of-flight/quadrupole ion trap time-of-flight mass spectrometry (TOF/QIT TOF MS), and other analytical techniques that are discussed in detail in the further sections. The Dissertation is presented as a collection of five works: Inorganic materials (4 works) and Organic molecules (1 work). A) Mass Spectrometry of Inorganic Materials: Nanocomposites (1) The first work deals with laser ablation synthesis (LAS) of carbon-phosphides from graphene/nanodiamond-phosphorus composite precursors. It was observed that several novel series of carbon-phosphide clusters were generated via laser desorption ionization (LDI) or LAS from graphene or nanodiamond composites with red/black phosphorus or with phosphorene. Chalcogenides (2) This study describes the generation of clusters from Ge-Bi-Se thin films and from Ge, Bi, and Se elemental mixtures via LA. Finally, the stoichiometry of generated clusters from thin films was compared with the stoichiometry of those detected from the elemental mixtures. Furthermore, the structures of some selected binary and ternary clusters were calculated using density functional theory to understand the geometry of the generated clusters. (3) This work focuses on the generation of bismuth-selenide clusters from the mixtures of elements and from Bi2Se3 crystals and/or thin films using LDI and/or surface-assisted LDI. The generation of such clusters from the surface of graphene and nanodiamonds was studied. It was found that no remarkable difference with comparison to the metal surface was observed. (4) In this work, laser ablation of Ga-Sb-Te chalcogenide thin films was monitored with the quadrupole ion trap time of flight mass spectrometry (QIT TOF MS). Several series of clusters were identified. The fragmentation was diminished by covering the surface of thin films with paraffins, glycerol, or trehalose sugar thin layers. B) Mass Spectrometry of Organic Molecules: (5) This work deals with the evaluation of black phosphorus (BP) for improved discrimination of intact cells via mass spectrometry. The discrimination of three cell lines was significantly improved when PCA of mass spectra acquired using the BP enriched sinapinic acid (SA) matrix as compared to the common SA matrix alone was performed. Furthermore, BP enriched &alpha-cyano-4-hydroxycinnamic acid (CHCA) and/or SA matrices enhanced significantly the sensitivity of various biomolecules (amino acids, peptides, and proteins or intact cells) detection. Concluding, it has been demonstrated that LA/LDI with TOF/QIT TOF MS and/or MALDI/SALDI MS are powerful techniques for the generation of clusters and characterization of inorganic materials as well as biomolecules.