Noise emission is an important problem of vehicles. An important part of the general noise of the vehicle, which is called pass-by noise, is composed of the wheels and the engine. In this study, it was aimed to design a wheel arch liner (WAL) that can absorb the sounds coming from the wheels of the vehicles by creating micro-perforated panel (MPP) structures. While examining the diameters, pattern, and frequency of the holes in the MPP structures within the scope of the research; The effect of the cavity, which can be left behind the wheel arch liner structure to be used in the vehicle, on the acoustic absorption values was also included in the scope of the research, and studies were carried out to reduce the acoustic emission. In order to observe the effect of this cavity, 2 different cavity sizes (18-28 mm) were used with a without cavity MPP structure. In the results of the research, the highest acoustic absorption value (Sα) was observed as 0.97 in the sample with 7% hole density and 3 mm hole diameter. In addition, when the cavity behind the MPP structure is examined, the best Sα value was found in the sample with an 18 mm cavity. This research, which sought to reduce pass-by noise, revealed the potential of integrating MPP structures into wheel arch liners to reduce wheel noise