Unconventional parts of fruits and vegetables represent a rich source of diverse phenolic compounds (PC) and antioxidant fibers, well known to have bioactive properties such as antioxidant, antimicrobial, antifungal and antitumoral activity. Pineapple processing generated a large amount of residues (49%) that are discarded even if have equivalent or higher content of nutrients and phytochemicals than the edible parts. The objective of this work was to evaluate the flavonoid content and profile of pineapple crown flour (PCF) by metabolomics tools. The pineapple crowns were collected in hortifrutis unit during three days successively. The samples were washed, fractionated, dried in a ventilated oven (65 °C/10 h and 90 °C/1 h), ground and stored. Free PC were extracted separately with ethanolic and methanolic solutions (80%) and bound PC (pellet) after alkaline and acid hydrolysis. The total phenolic content (TPC), the total flavonoid content (TFC) and the antioxidant activity (ORAC and DPPH methods) were determined on a microplate reader. The complete PC profile was analyzed by UPLC-MSE in negative mode (ESI-) and data were processed using Progenesis QI applying: exact mass error (10 ppm), isotope similarity (80%), fragmentation score, CV and reproducibility (3/3). PCF had great antioxidant activity, especially in bound extracts (DPPH 244.67±39.30 and ORAC 44995.51 ± 5242.72 µg TE.g-1 flour), without difference between the two alcoholic extractors. The PCF showed high content of TPC (18.68±0.85 mg GAE.g-1. PCF extracts showed differences in TFC, with values between 0.59 ± 0.13 and 4.92 ± 0.53 mg CE.g-1 of flour. Globally, 177 PCs were tentatively identified, mainly in bound form (115) than in free form (62), with 14 common compounds in both extracts, such as p-coumaric, sinapinic, caffeic and ferulic acids. Most part of PC identified were flavonoids (68), followed by phenolic acids (63), other polyphenols (34), lignans (10) and stilbenes (3). The main flavonoids found in both, free and bound extracts were: apigenin 6-C-glucoside, genistin, quercetin 3-O-glucoside, kaempferol, daidzin, nepetin and 3,7-dimethylquercetin. PCF showed important antioxidant activity and interesting profile of flavonoids and a rich source of bioactive compounds showing great potential of use, contributing to the reduction and valorization of agroindustrial residues.