Based on the approach of Situational embedding, we discuss the impact of enterprises’ institutional status and cognition on their choices of horizontal integration management mode in the circumstances of Chinese market by adopting Industrial Equipment Installation Company of Guangdong Province as a case. The results show that when an enterprise enters regional markets where its institutional status is high, it has greater autonomy to choose a management mode for the pursuit of horizontal integration benefit. But it has to meet the local requirements in choosing a management mode when its institutional status is low. Besides, top managers’ cognition of the market environment and its own status has more direct influences on the choices of management mode in Chinese enterprises’ horizontal integration.