[in Persian with English abstract: ] This study aimed to identify specific phytochemical properties associated with five distinct lichen ecotypes of Ramalina farinacea from different regions in Iran: Golestan (Kordkooy, Gorgan), Mazandaran (Farim and Galugah), and Semnan (Shahrud, Kalpush region). In order to determine intraspecific chemotype diversity, qualitative differences in chemical profiles were investigated using liquid chromatography-tandem mass spectrometry (LC-ESI/MS/MS). The following chemicals were identified based on LC/ESI-MS/MS results: (1) Atranol, (2) Divaric acid, (3) Evernic acid, (4) Ramalinaic acid, (5) Squamatic acid, (6) Sekikaic acid, (7) 4’-0-Methyl norsekikaic acid, (8) Glomellonic acid, (9) Conprotocetraric acid, (10) Usnic acid, (11) Nephrosterinic acid, (12) Dihydroxyoctadecenoic acid, (13) Hypoconstictic acid, and two unknown substances. Statistical analyses using Ward's method in SPSS were performed based on quantitative and qualitative traits. The dendrogram revealed two main clusters, with Farim and Galugah closely grouped in one subcluster, Gorgan in another subcluster, and Shahrud and Kordkooy in a separate cluster. Correlation coefficients between the studied traits showed a positive correlation of slope direction, altitude, humidity, maximum and mean temperature with the chemotypes. These findings confirm the observed variations in the chemical profiles of the lichen ecotypes. Keywords: Altitude, Chemical profile, Ecotype, Lichen, Phytochemistry, Slope direction.