The Mexican international has made the move from Holland after Eindhoven failed to qualify for the Champions League group stages, losing out to Basel in the qualifiers.
Napoli have been in the lookout for a wide player for the entirety of the summer and the club have moved quickly to secure the services of Lozano, after Nicolas Pepe snubbed a move to Italy in favor of a big-money move to Arsenal.
Lozano is a household name in the Eredivisie but the tricky winger announced himself to the footballing world in the 2018 FIFA World Cup, famously scoring a goal as Mexico downed Germany in the group stages.
Napoli have shattered their transfer record to acquire his services and the transfer fee is believed to be in the region of £34 million.
The 24-year-old becomes Napoli's ninth signing of the summer and his arrival could signal the end of the their transfer business in 2019.
Lozano reportedly arrived in Naples earlier this week to undertake a medical and discuss personal terms and his move to the Italian club has now been made official.
The tricky winger, fondly referred to as Chucky, is the first Mexican to represent Napoli and in doing so, he has become the most expensive purchase in the club's history.
He enjoyed a fruitful time in the Eredivisie, registering 40 goals and 23 assists in 79 games and played a pivotal role in PSV title triumph in the 2017/18 season.
Lozano has been capped 38 games for the Mexican national team and the former PSV man has nine goals to his name since making his debut in 2016.
Lozano's arrival is set to bolster Napoli's firepower up front and the Italian giants are well equipped to mount another title challenge.