Abstract This research uses explanatory case study method with a qualitative approach. It highlights the positioning dynamics on party model of Islamic parties, PPP and PKS in the post-New Order elections. By using Andre Krouwels framework on party models, the paper argues that PPP and PKS shifted their party model positioning from mass party in 1999 legislative election, then changed or transformed in, to catch-all party post-1999 legislative elections. The thesis was found by exploring four basic things of Krouwels party model framework, which are: (1) what/who is the main support base; (2) how is the pattern of elite recruitment created (especially those of legislative candidates); (3) what is the foundation of their electoral political struggle; and (4) where does the party competition goes (centripetal or centrifugal). I found quite interesting thing when exploring the political behavior of PPP and PKS post-1999 legislative election. Based on field data, I found ambiguity inside the parties related to the foundation of their political struggle in the realm of electoral politics. On the one hand, they are moderate-patterned, presenting themselves as the center party, open, and their campaign is seen to fight for universal issues that tend to be normative. However, on the other hand, the parties retain their religious conservatism related to project of Islam formalization in the state, society and the whole system, although it is done for internal circles only.