This research aims at clarifying the effect of confidence of the Parliament upon the ministry in terms of its inauguration and continuation in the State rule. In fact, the ministry, in several systems, particularly the parliamentary and mixed systems, cannot exercise its constitutional competence except after obtaining of confidence of the Parliament. At the same time, its continuation in the State rule depends on this confidence which has a clear effect in relation to implementation of the political ministerial responsibility; including the individual and solidarity responsibility. This requires to distinguish between the various demands of confidence which may be divided into two main sections. The first is the demand of granting the confidence which is mandatory after the establishment of the government (investiture vote). The second is optional when the government or the prime minster raises the question of confidence in particular occasions as the proposal of drafting a law or discussion of the Government Statement (vote of confidence procedure). In case of refusal of the Parliament, this leads to withholding of confidence (not withdrawal of confidence). This also lead to the procedure of vote of no-confidence (withdrawal of confidence) which asked by the members of Parliament in face of the government or the minister.