Hyundai has been airing the commercial since late December which shows a slow-motion video of a head-on collision between the two cars. A subtitle says the test was conducted in November at the Hyundai R&D center in Namyang, Gyeonggi Province.
Audi Korea said it is somewhat surprised to see it on TV without any prior notice from Hyundai.
A spokesman for Audi Korea said: "We are trying to find out what happened and are considering taking legal action."
Hyundai Motor only refers to the victimized car as a "European luxury car" in the advert but internet users immediately identified it as an Audi A8.
A Hyundai Motor spokesman said the ad was not intended to show that Genesis was structurally stronger than an A8.
He said: "We didn't say which one ensures more safety. We intended to give the message that Hyundai Genesis is now level with European luxury cars and that it can match them face-to-face."