The institutionalization of a political party is one of the factors that affect the stability of the votes or the number of seats of a political party in the election.In the 2014 legislative election, the votes or the number of seats of the Democrat Party of the Province of Lampung decreased compared to the 2009 legislative election. However, the vote or the number of seats in the 2014 legislative election is still fairly stable when compared with the vote or the number of seats of the Democrat Party in other regions.The stability of the votes or the number of seats of the Democrat Party of the Province of Lampung in the 2014 legislative election is interesting to study to investigate whether the stability is influenced by the factor of the institutionalization of the party or be influenced by other factors such as patronage and clientelism.This research uses descriptive method with qualitative approach. In this study, the researchers also conducted an analysis of the index of institutionalization of political party to determine the level of institutionalization of the Democrat Party of the Province of Lampung.This study takes the research sites in the Province of Lampung with the Democrat Party as the research object. This study concludes that: First, the level of institutionalization of the Democrat Party of the Province Lampung is in the medium category.Second, the stability of the votes of the Democrat Party of the Province of Lampung is not solely influenced by the institutionalization of the party, but is influenced by two other factors which are more dominant, namely the practice of patronage and clientelism in governor election and legislative election which are carried out simultaneously and the practice of patronage and clientelism performed by the Democrat Party candidates. The recommendation of this study is that the Democrat Party of the Province of Lampung must immediately resolve the flaws in the institutionalization dimension, especially in the number of the power of members or cadres, the number of the networking of mass organization or organizational wing of the party, so that in the future, the potential of the power of the members or cadres and mass organizations or organizational wing of the party can run maximally so the party machinery can operate more effectively during the elections. Keywords: Institutionalization of the party, Patronage, Political clientelism.