A 4D hyperspectral imaging (HSI) dataset of lichen specimens. This dataset was acquired as part of Chilingaryan et al. (2026). When using it, please cite the original article as follows: Chilingaryan, N., Gasparyan, A., & Sarvazyan, N. (2026). Multi-Excitation Hyperspectral Imaging Toward Improved Lichen Identification. 2025 15th Workshop on Hyperspectral Imaging and Signal Processing: Evolution in Remote Sensing (WHISPERS). Accepted. Materials and Methods Biological Samples Lichen specimens were provided by Takhtajyan Institute of Botany, National Academy of Sciences of Armenia. Species were identified using standard methods and based on commonly used identification guides and keys. The nomenclature follows Index Fungorum (www.indexfungorum.org). Specimens were cut into ~ 5 × 5 mm pieces and arranged in a grid (Photo_SamplePrep.jpg) Each specimen is described in Metadata_Classes.csv, and can be tracked in HSI images via Mask_Manual.png 4D Hyperspectral Imaging (HSI) For illumination, WeeLED wavelength-switchable light source was used (Mightex Systems, WLS-23-A) containing eight UV-VIS LEDs with wavelengths ranging from 310 to 430 nm and the broadband 5500K cool white LED. Hyperspectral images were acquired within 420–720 nm range with either 2 or 10 nm spectral resolution using the Nuance FX Imaging System (CRi, Woburn, MA, USA) Details of imaging conditions are available in Metadata_HSI.csv The data are available in both the original .im3 and converted .tif formats under the HSI directory (when unzipped). References Chilingaryan, N., Gasparyan, A., & Sarvazyan, N. (2026). Multi-Excitation Hyperspectral Imaging Toward Improved Lichen Identification. 2025 15th Workshop on Hyperspectral Imaging and Signal Processing: Evolution in Remote Sensing (WHISPERS). Accepted.