Since 2005 the societies quoted have started to apply the international financial reporting standards IAS/IFRS for the drawing up and the publishing of the balance sheet. The objective of the IFRS, except for the fact that they aim at the harmonization of the ways of drawing up the financial statements, is that of drawing near the patrimony value close to its current value.Applying the standards IAS 32 and IAS 39, which introduce, in particular a new classification of the financial instruments has new significations within the accounting administration of the security operations made by the use of the derived financial instruments. Particularly, the IAS 39 focuses on the assessment of the financial instruments specifying the application and utility area of the just value, as well as of the evaluation criterion. We will try to detail the situations when an assessment at the just value takes place and to the acquisition cost or the liquidated cost underlying in the same time all the security operations at the accounting level, described in this standards