This paper presents a new concept of high-resolution direction-of-arrival (DoA) estimation in orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) radar with integrated communication system (RadCom) for automotive applications. High-resolution DoA estimation is an important requirement for automotive radar systems, especially in multi-target scenarios that require higher target separation performance. This paper introduces a subspace-based procedure for high-resolution DoA estimation for closely spaced targets in uncorrelated and partially correlated signals, and allows better DoA estimation in coherent signals. This procedure integrates the use of the radar signal together with the communication signal received from another user (one of the targets to be estimated).