In this study, dispersive liquid-liquid microextraction (DLLME) and hollow fiber based liquid-liquid-liquid microextraction (HF-LLLME) coupled with reversed phase-high performance liquid chromatography-diode array detector (RP-HPLC-DAD) were applied for simultaneous extraction and determination of three narcotic drugs (Alfentanil, Fentanyl, and Sufentanil) in biological samples. In the DLLME method, 2000 ?L dispersive solution, containing 1838 ?L disperser solvent (methanol) and 162 ?L extraction solvent (chloroform) was injected rapidly into an aqueous solution contains narcotic drugs with a 2500 ?L syringe (Gastight, Hamilton). Then the mixture was centrifuged at 3500 rpm for 5 min, and the sedimented phase was completely transferred to another test tube with conical bottom using a 100 ?L syringe. The organic solvent was evaporated by a calm flow of nitrogen gas and the residue was redissolved in 12.5 ?L mixture of acetonitrile-water (50:50), and 11 ?L of the solution was injected into HPLC. The effects of several important parameters influencing the extraction efficiency including type and volume of the extraction solvent, type and volume of the disperser solvent, concentration of NaOH, and salt addition were investigated. Optimum conditions were achieved as: chloroform as extracting solvent, methanol as disperser solvent, extracting solvent volume 162 ?L, volume of disperser solvent 1838 ?L, 0.05 M NaOH, without salt addition. Under optimal condition, the limits of detection were ranged from 0.4 to 1.9 ?g/L. The intra-day and inter-day precisions were in the range of 1.2-3.0 % and 14.2-15.9 %, respectively. The enrichment factors and correlation coffieients ranged from 275-325 and 0.9980-0.9984, respectively. The applicability of the proposed method was demonstrated by analyzing biological samples (plasma and urine).In the HF-LLLME,the effects of several important parameters influencing the extraction efficiency including organic solvent type, concentration of NaOH as donor solution, concentration of H 2 SO 4 as acceptor phase, salt addition, stirring rate, temperature, and extraction time were investigated and optimized. Under the optimized conditions (isoamyl benzoate as organic solvent, 0.5 M NaOH as donor phase, 0.05 M H 2 SO 4 as acceptor phase, stirring rate of 1200 rpm, 20 min extraction time, no salt addition, at 45 o C), the limits of detection were ranged from 1.1 to 2.3 ?g/L. The intra-day and inter-day precisions were in the range of 2.0-4.1 % and 3.3-10.1 %, respectively. The enrichment factors and correlation coefficients ranged from 190-237 and 0.9971-0.9981, respectively. The applicability of the proposed method was demonstrated by analyzing biological samples (plasma and urine).