The 26-year-old joins the Whites on a four-year contract for an undisclosed fee, subject to a work permit and international clearance.
Standing at 6ft 3in, Bornauw is known for his powerful and commanding presence at the back, particularly his strength in aerial duels.
His arrival marks Leeds' third signing of the summer transfer window as they look to bolster their defensive options.
Bornauw began his professional career at Belgian giants Anderlecht, graduating from their academy and making his first-team debut at 19.
He gained experience in both the Belgian Pro League and UEFA Europa League before moving to the Bundesliga in 2019 with FC Koln. There, he made 57 appearances and scored seven goals, including a memorable goal on his Bundesliga debut.
Following his successful spell in Cologne, Bornauw transferred to Wolfsburg, where he went on to feature nearly 100 times in both the Bundesliga and UEFA Champions League.
At international level, Bornauw has represented Belgium across various youth categories, underlining his pedigree as a promising talent from a young age.
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