Latin America witnessed a region-wide political turmoil throughout the year of 2019，caused by social conflicts or political crisis in a number of regional countries. It is closely related to deeply rooted institutional weakness in those countries. Their democratic institutions are resulted from the democratization initiated in the late 1970s and featured by conservativeness and elitism. Nowadays regional democracies are mainly categorized as low intensity democracy due to a variety of institutional deficiencies. The combination of presidentialism and the fragmentation of political parties is viewed as a major factor impairing governability. Political parties are blamed for failing to correspond to political demands of the emerging middle class. Against the background of economic depression and social discontent，institutional weakness is an especially notable challenge confronting regional countries.