The 21-year-old joined Sunderland last summer on loan from Bundesliga side Union Berlin.
Speaking ahead of pre-season, the forward said he was happy to be back.
“I’m very happy to be back and I’m excited about the new season, especially competing and proving myself in a new league.” the German told Sunderland club media.
“Last season was sometimes challenging for me, as I had to adapt to a new country and a new style of football.
“I really enjoyed being a part of Sunderland and I had some good moments on the pitch, but I was unwell twice and I felt that impacted my progress.
“I was then out of the team because my team-mates were performing very well, but that’s football and the most important thing was achieving promotion.
The ultimate Sunderland end of season quiz – We’ll be impressed if you score above 80% on this
“It was an amazing day at Wembley Stadium and it made me hungry to enjoy more success here, so I’m feeling good and I’m ready to give one hundred per cent for the team.”
On loan in 2021/22, Leon Dajaku scored four goals and registered four assists in 27 appearances for the Black Cats.
The forward’s and Sunderland’s Championship campaign is set to kick off on the 31st July, with a home match against Coventry City.
Leon Dajaku will be hoping he can contribute for Sunderland a bit more next campaign.
Although he racked up 27 matches last campaign, only 22 of these were in League One.
As the German forward outlined, illness and selection issues hampered his contributions, but it will certainly be interesting to see if he can force his way into Alex Neil’s plans this pre-season.
If he can at least play a bigger part, it may ease some of the burden placed on Ross Stewart last campaign.