Quantum entanglement in optomechanical systems plays a vital role in the progress of quantum science and technology, such as exploring fundamental physics and quantum information processing. Although the physical law of quantum mechanics does not specifically limit the size of objects that carry the entangled states, the experimental preparation and detection of quantum entanglement in the macro world still face great challenges. Fortunately, with the practical advances in recent years, several pioneering works have demonstrated non-local correlation and entanglement among mechanical oscillators or between electromagnetic fields mediated by a mechanical oscillator. In this perspective, we summarize the theoretical and experimental progress related to the macro entanglement states in optomechanical systems and the outlook on its future direction and potential applications.