Mastrorillo has been working mainly on long term documentary projects, devoting himself to the deep consequences of war and natural disasters and their aftermaths on society. 

His photographs have been published in numerous national and international magazines and they have been featured in numerous solo and group exhibitions.

His major awards include: the World Press Photo, the Pictures of the Year International (POYi, third prize as Magazine Photographer of the Year) and the Best of Photojournalism (third prize as Magazine Photographer of the Year),  New Photography Talent FNAC, the PDN Photo Annual, the International Photographer of the Year at the 5th Annual Lucie Awards, the Sony World Photography Awards, a nomination for the Prix Pictet 2009 “Earth”, the Aftermath Grant (finalist, 2011). His ongoing project “Il Mare siamo Noi (The Sea os Us)” was shortlisted for the Vevey Images Grant 2015 and 2017.  “Aliqual”, his body of work on the earthquake aftermath in l’Aquila, Italy, has been nominated for the Prix Pictet 2015 “Disorder”.

Currently Mastrorillo is working on his next project “Il mare siamo Noi (The Sea is Us)” about the assets seized or confiscated to mafia organizations in Italy.

He was Talent Manager at LUZ, one of the main photo agencies in Italy and a Leica Ambassador. Since 2008 he develops his work as a teacher cooperating with the Scuola Romana di Fotografia (Rome), the Luz Academy (Milan), the Leica Akademie and the Door Academy (Rome).

Mastrorillo is a member and a cofounders of door, a Roman factory working with photography, educational, publishing and talent scouting.