Abstract: Microcystins are common hepatotoxic cyclic toxins released from blue and green algae, which can harm to animal and human health．It is important to establish an accurate and rapid method for the safety of aquatic products. All the parameters of sample preparation and instrumental methods were optimized. Seven microcystins (LR, RR, YR, LW, LA, LF, and LY) in aquatic products were determined simultaneously by liquid chrometography tandem mass spectrometry. Solid-phase extraction(SPE) and matrix solid-phase extraction (MSPD) were adopted for sample preparation. For SPE method, the LOQ is 0.5 μg/kg, and the recoveries are between 75% and 106% with RSD less than 20%. For MSPD method, the LOQ is 2.5 μg/kg, and the recoveries are between 73% and 93% with RSD less than 16%. This method is suitable for daily inspection and confirmation of microcystins in aquatic products.