The present invention concerns Y-type FAU zeolites with hierarchical porosity having an Si/Al atomic ratio strictly greater than 1.4 and less than or equal to 6, having controlled and optimised crystallinity, and having mesoporosity such that the mesoporous outer surface area is between 40 m2·g−1 and 400 m2·g−1. The present invention also concerns the method for preparing said Y-type FAU zeolites with hierarchical porosity.