Integrated sensing and communication (ISAC), as a rapidly advancing technique, is proposed to address both the communication and sensing problem in a unified framework over the millimeter wave (mmWave) frequency bands. In this paper, a cost-saving bi-static architecture is designed for the mmWave ISAC system, and a corresponding effective estimation scheme is proposed utilizing the canonical polyadic (CP) decomposition, where a heterogeneous placement of stations is adopted, and both communications terminals (CTs) and passive targets (PTs) are jointly considered.