The study presented considers the vegetation in the historic center of Merida, Yucatan, is an important component of the natural heritage that contributes to determine the culture and character of the region. The primary objective is to demonstrate the relevance of historical heritage and vegetation in the same context, considering the valuation of public spaces with good environmental quality positively impacts the quality of life of society. Reconcile the preservation of the environment and the historical and artistic heritage in a global, multicultural era, is a challenge. As different avenues of research developed in one of the oldest, representative and populated areas of the historic center of Merida; The San Sebastian and the Chapel of Santa Isabel. The research, helped to confirm a growing dynamic vegetation loss, impacting environmental quality. To obtain a floristic survey data allowed to know the number and type of species was developed. This is not only important for the natural heritage and historic environmental surroundings, but in the case of the city of Merida can help to mitigate the high temperatures.