Seismic method is a good geophysical method in imaging the subsurface conditions using the principle of seismic wave propagation. This method is often used in hydrocarbon exploration. One important step in hydrocarbon exploration is seismic interpretation. In the stages of seismic interpretation, a good basic knowledge of geophysical and geological knowledge is needed regarding the existence and characterization of hydrocarbon reservoirs. One method used in interpreting seismic data is the acoustic impedance inversion method. In this study, 2D seismic inversion was carried out to determine the reservoir characteristics of the MCL-1 well in the Nias basin. This study uses model-based on inversion which aims to obtain the value of acoustic impedance which is useful for the identification of distribution, porosity values and reservoir conditions of the target zone. The results obtained are the target reservoir zone at a depth of 6649-7434 feet or 1705-1810ms for MCL-1 wells with a range of acoustic impedance values of 25556 ((ft/s) * (g/cc)) - 46885 ((ft/s) * (g/cc)) with the type of rock that fills the reservoir is the type of limestone rock. The correlation value for model-based inversion has a relatively small error. This can characterize the hydrocarbon reservoir well.