The root of idea of conversion in procedural behaviours and actions extends into Romanian legal thought, which know the idea of conversion; praetor contributed with an important role in its spread. Because of that, many of laws affected included French and Egyptian law, where it becomes a general theory within the modern law theories in the objective and procedural filed. That was with intent reducing of the formalism and facing the practical needs with consideration of achieving justice. Indeed, the idea of conversion was knew by the Egyptian legislator in the field of the objective law, firstly. Where it mentioned in legal section (144) of the civilian law no. (131) in 1948. Then, the legislator transfers the idea into the field of procedural law, where the legal section (24) of Egyptian civil and commercial pleadings law no. (13) in 1968. The subject that in it the idea of conversion in Egyptian legislation had objective legislative cover and procedural (formal). For activating the idea of conversion of criminal procedure in Iraqi law to accelerate procedures of criminal case, and because of the Iraqi legislator did not take the idea of conversion except in the field of objective law where the legal section (140) of civil law no. (140) in 1951. As a foundation on that the hypothesis concept of this research based on (indeed the absence of the idea of conversion in the Iraqi procedural laws does not mean it is invalid, because it is a one of the items of the general legal regulations. The researcher goes to invite the Iraqi legislator to make the law of civil pleadings included with a similar text to that the Egyptian legislator used in civil and commercial pleadings law. Then, to proceed after it accepted from the judgment of the first section of the Iraqi civil pleadings law, which made this law as a reference to all of the pleadings and procedures laws into actions of the idea of conversion of the criminal procedure in the field of law of origins of criminal trials.