The extraction and analysis of free fatty acids (FFAs) in the whole natural plants are reported. The aminopropyl-functionalized SBA-15 was designed to increase the efficiency of the matrix solid-phase dispersion (MSPD) extraction method. MSPD extraction was performed using to extract FFAs via acid-base interactions. The optimum parameters for the MSPD extraction were N-SBA-15 30 mg, grinding time 120 s and elution solvent methanol-HCl (6:4, v/v). After extraction, the FFAs were analyzed by HPLC with fluorescent labeling. The reaction of the labeling agent, 2-(9-oxoacridin-10(9 H)-yl) acetohydrazide, with FFAs proceeded easily and quickly (within 20 min) in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride as the condensing agent. The derivatives had excellent fluorescence properties with excitation and emission wavelengths of 260 and 430 nm, respectively. Good linear correlations were observed for all FFAs, with correlation coefficients >0.996. When 20 mg of sample were used for the analysis, the detection limits at a signal-to-noise ratio of 3 were in the range 0.21-1.20 μg g-1. The FFAs in the roots, stems, leaves and peel of Trichosanthes kirilowii Maxim were determined using the developed method.