Quinoa (Chenopodium quinoa), amaranth (Amaranthus caudatus) and buckwheat (Fagopyrum esculentum) represent the main protein source in several diets, although these pseudocereals are not currently present in the FCDB nutrient profile information. The aim of this work is to characterise the AA profile of these pseudocereals and compare them with rice. Total protein content revealed to vary from 16.3 g/100 g (quinoa Salta) to 13.1 g/100 g (buckwheat) and lower values were found in rice samples (6.7 g/100 g). For pseudocereals the most abundant essential AA was leucine. Quinoa-Salta evidences the highest leucine content (1013 mg/100 g) and the minor methionine content (199 mg/100 g). Buckwheat was the cereal with the highest phenylalanine content (862 mg/100 g). Rice (Oryza sativa) presents the lowest content for all AA. Results showed pseudocereals as the best source of AA. EuroFIR guidelines where strictly followed and proved to be a crucial tool to guarantee data interchangeability and comparability.