The invention discloses a microarray chip without solid walls based on LSPR (Localized Surface Plasmon Resonance) and application thereof. The substrate of the microarray chip is in a hydrophilic and hydrophobic mode and comprises a base, a plurality of hydrophilic regions and hydrophobic regions, wherein the hydrophilic regions are arranged on the base; the hydrophobic regions separate the hydrophilic regions; the surfaces of the hydrophilic regions are provided with metal nanometer material layers with local area surface plasma resonance attributes; the outer regions of the hydrophilic regions are not provided with the solid walls; the surfaces of the hydrophobic regions are provided with hydrophobic material layers. The microarray chip disclosed by the invention can be obtained by combining a peculiar affinitive molecule for detecting a substance to be detected on the substrate provided by the invention. The microarray chip disclosed by the invention has the advantages of easiness and convenience for use, low detection cost, accurate result, reusability, and the like, can be used for detecting multiple substances, such as micromolecules, heavy metal ions, proteins, bacteria, viruses, and the like, and has wide application prospect in the fields of medical health, environmental monitoring, scientific experiments, and the like.