The winger made a good impression during his loan spell last season and the newly promoted side have not made the move permanent.
The 24-year-old picked up 6 goals and 6 assists in 28 Championship starts last season.
El Ghazi will be looking to prove himself in the Premier League now.
Aston Villa star Jack Grealish took to Twitter to share his reaction to the signing.
His tweet read:
Dean Smith needs to keep his key players in order to do well in the Premier League and the El Ghazi transfer was a no brainer.