Synthetic cannabinoids (SCs) are the most rapidly growing class of recreational designer drugs. The rapid growth in popularity of SC use among teens and adults is of serious in our country as all of the world. These products are saturated in various plants crumb in order to make herbal appearence. They are not for human consumption and also their chemical structures are rapidly evolving. They are known as "Bonsai" in Turkey. 5F-ADBICA and 5F-NPB-22 are the two most commonly detected compounds in seized herbal products by police forces. The aim of this study was to determine and validate 5F-ADBICA and 5F-NPB-22 in whole blood and urine by LC/MS-MS. No method exists in the literature for the simultaneous determination of these new-generation SCs. 250 mu L blank blood was transferred to 16 x 100-mm test tubes. Extraction was performed with 2 mL acetonitrile:ethyl acetate (25:75). The tubes were capped and rotated for 15 min. The samples were then centrifuged for 10 min at 3500 rpm. The organic layer was transferred to other tube and was evaporated to dryness at 45 degrees C under a stream of nitrogen. 0.5 mL of urine samples, 1.5 mL ice-cold acetonitrile and 0.5 mL of a 10 M ammonium formate solution were added. The mixture was shaken, centrifuged, and 1 mL of the organic layer was transferred into a separate vial and evaporated to dryness under a stream of nitrogen. The dried extracts were reconstituted with mobile phase A. The chromatographic separation was performed with a pentafluorophenylpropyl (PFPP) column (Allure 50 x 2.150 mm i.d., 5 mu m, Restek, Bellefonte, PA, USA) using a gradient binary with 10 mM ammonium formate (A) in ultrapure water and methanol (B). The run time is 20 min. The method was validated in terms of limits of detection (LODs) (0.01-0.12 ng/mL) and quantification (LOQs) (0.03-0.36 ng/mL), extraction recovery (ER) (77.4-97.3%), matrix effect (ME) (63.3-83.6%), linearity, intra- and interday precision (CV < 20%) and carryover. A simple, cost-effective, and accurate LC/MS-MS method has been developed for the simultaneous quantification of 5F-ADBICA and 5F-NPB-22 in whole blood and urine. The newly developed analytical methods allow the analysis of new-generation synthetic cannabinoids.