The samples were collected from the Batak mountain, Bulgaria. Three popular wild edible mushroom species Boletus pinophilus, Cantharellus cibarius and Craterellus cornucopioides were analyzed for their free amino acid compositions by Q Exactive mass analyzer equipped with TurboFlow LC system and IonMax II electrospray ionization module (ThermoScientific Co, USA). Data acquisition and processing were carried out with XCalibur 4.2 software package. Twenty free amino acids: histidine, arginine, aspargine, glutamine, serine, aspartic acid, glutamic acid, threonine, glycine, proline, tyrosine, valine, methionine, leucine/isoleucine, phenylalanine, ornithine dihydrochloride, tryptophane, lysine, 4-hydroxyproline and γ-amino butyric acid, were determined. The total free amino acid (TAA) contents were from 26.46 mg kg-1 in Cantharellus cibarius to 44.18 mg kg-1 in Boletus pinophilus. The ratio of EAA to TAA were from 0.04 mg kg-1 in Cantharellus cibarius to 0.14 mg kg-1 in Craterellus cornucopioides. Glutamine, arginine, ornithine, and serine were among the most abundant amino acids present in all species. The results showed that the analyzed mushrooms contained a significant amount of free amino acids which may be important compounds contributing to the typical mushroom taste, nutritional value, and potent antioxidant properties of these wild edible mushrooms. Furthermore, the principal component analysis (PCA) showed that the accumulative variance contribution rate of the first two principal components reached 90.57%.