The IBO champion dominated from the off, dropping Yildirim in the first with his trademark uppercut before putting together a mass of punches in the third to soften the Turkish challenger up.
In the end, it was one massive shot that halted the contest as Yildirim went down in sickening fashion and was in no position to continue the mismatch.
Eubank moves on to face the winner of George Groves v Jamie Cox next week and will be a considerably shorter price to lift the Ali Trophy on the back of the result.
On the undercard, Stefan Haertel earned a hard-fought majortiy decision win over Viktor Polyakov as the super-middleweight continued his undefeated run.
The 29 year-old, who defeated Patrick Mendy in June, was granted the tightest of victories as judges carded 96-94 (twice) in his favour with the other seeing it 95-95 a draw.
British prospect Zach Parker celebrated signing a deal with promoters Sauerland by helping himself to a 14th career win on points over Matingi Kindele.
Former world cruiserweight champion Firat Arslan scored a seventh round stoppage over Alejandro Valori to pick up a 41st career victory. Arslan is aiming for one more crack at a title in 2018 before the veteran eventually hangs up his gloves.
Leon Bauer suffered the first blemish on his thirteen fight career after struggling to a draw with Atin Karabet, before Timo Schwarzkopf saw out an eight round decision triumph over Massimiliano Ballisai.
In the first of a host of super middleweight contests, Denis Radovan beat Tiran Metz on points over eight rounds to make it seven straight wins as a pro, whilst heavyweights Burak Sahin and Albon Pervizaj both won their respective encounters expectedly.