Magilton is optimistic the 28-year-old former Avellino forward has the credentials to succeed in the Championship.
"Alessandro has done well with us during his trial period," Magilton told the club's official website. "He's a natural goalscorer and we're delighted to add him to the already healthy attacking options we have at our disposal.
"He'll take time to settle over here, but we're really excited by his arrival."
Pellicori began his career at Cosenza and has had spells at Lecce - for whom he played in Serie A - Grosseto, Piacenza, Cesena and Avellino.
Pellicori scored as QPR defeated Kettering 2-0 on Wednesday night.
The 28-year-old netted from close range after Heidar Helguson had headed Rangers in front.
"It was a terrific workout for us against stern opposition," added Magilton. "We've got to see the trialists again, some of the experience lads got important game time under their belts and the young lads showed glimpses of what they can do.
"All in all it's a pleasing night - we scored two very good goals and moved the ball very well at times. It's all preparation for August 8."
Magilton is pleased with how his squad is shaping up, adding: "I think the squad is very competitive now. We've got a good group.
And it's an obvious thing to say, but the more quality you've got at the football club, the better."