Multiple-input multiple-output (MIMO) systems require numerous analog-to-digital converters (ADCs) to support their matched filtering system, resulting in increased system cost and significant demands on transmission and storage resource. In this paper, we investigate the mixed-resolution ADCs-based structure for the bistatic MIMO radar system as a trade-off between the system performance and cost, where the entire receive branch is quantized in either low or high resolution. In bistatic MIMO radar, the direction information, including the direction of departure (DOD) and direction of arrival (DOA), is a key factor for locating the targets. Thus, the effects of exploiting mixed ADCs on the estimation accuracy are first investigated by analyzing the constructed system model. Then, the generalized Cramér-Rao bound (CRB) expression for the proposed scheme is derived, where the multiple target scenario is considered. Compared with the traditional and one-bit bistatic MIMO radar, the proposed scheme is a more effective and flexible solution. Furthermore, the selection of low-resolution quantized receive branches affects the DOA estimation performance, while the DOD estimation performance remains unaffected due to the entire receive branch quantization method. Numerical simulations are conducted to validate the proposed scheme and derived CRB expression.