The instrument of GC/MS/MS is similar to GC-MS, with an exception where a second phase of mass fragmentation is added .Here a second quadrapole is used in an instrument which is known as MS/MS. Here first the sample is subjected to gas chromatography and then placed in mass spectrometer where each ion is fragmented1 MS/MS consist of two quadrupoles :Q1 and Q2 , Q1 is last filter and Q2 is precursor ion. Both the quadruples are connected by a collision cell. They may be used for scanning or static mode which depends on the type of MS-MS analysis performed. Analysis include different types they are product ion scan, single reaction monitoring (SRM), Precursor ion scan and multiple reaction monitoring2. Finally the product ions are selected by the third quadropole (Q3) Mass filter . The target compounds are divided into six steps in the development of an MS/MS method. They are (1) specifying segment breaks (2). Selection of precursor ion (3) adjustment of Q value (4) examination isolation efficiency (5).Optimization of collision induced dissociation (CID) Voltage (6) Defining the scan range of the product3