The invention discloses a method for separating and purifying 
microcystin by utilizing series-connected 
solid phase extraction columns. The method comprises the following steps of: A, preparing an 
algae powder material, namely harvesting wild bloom-forming 
cyanobacteria or 
microcystis aeruginosa cultured indoors, cooling and 
drying to prepare dried 
algae powder; B, preparing the 
solid phase extraction columns, namely putting C18 fillers into 
Solid Phase Extraction (SPE) columns; C, extracting 
algae toxin, namely weighing the dried algae 
powder, adding 
methanol according to a proportion, putting on a shaking table and oscillating at 
room temperature; D, removing impurities, namely adding a supernatant and an organic extractant into a separating funnel according to a proportion, mixing and uniformly shaking, standing, and after 
delamination, removing the organic extractant; E, separating and purifying the algae 
toxin, namely after pretreatment, enriching sample solution by using pre-activated series-connected SPE columns, and eluting the 
toxin by using 20 to 50 percent 
methanol aqueous solution; and F, performing 
Methyl Cellulose (MC) detection. The method has good separation effect, large loading amount, is easy and convenient to operate and low in cost, can obtain two microcystins with the weight of more than or equal to 10 mg and higher purity each time, and the 
High Performance Liquid Chromatography-Ultra Violet / 
Diode Array 
Detector (HPLC-UV / DAD) detection can reach 85 to 90 percent.