A chromatography method for separating and purifying recombinant human lactoferrin from transgenic rice seeds, sequentially comprises the following steps of: 1) extracting recombinant human lactoferrin from transgenic rice seeds, to obtain crude extract containing recombinant human lactoferrin, 2) subjecting the crude extract containing recombinant human lactoferrin to cation exchange chromatography to perform primary purification, to obtain an elution fraction containing recombinant human lactoferrin; wherein: the cation exchange chromatography is performed on a weak cation exchange resin CM sepharose FF, the chromatography step comprises: 2A) equilibrating the chromatography column with 5-15 times column volume of buffer containing 10-25mM Tris, 10-25mM NaAC, 0-250mM NaCl, pH 6.0-7.5, at a flow rate of 50-200cm/h; 2B) using the crude extract of step 1) as a loading sample, wherein the sample having a conductance of 2-25ms/cm and a pH of 6.0-7.5; eluting impurities with an impurity-washing buffer, the impurity-washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 200-300mM NaCl, pH6.5-8.0, and the elution flow rate being 50-200cm/h; 2C) eluting the sample with a washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 400-650mM NaCl, pH 6.5-8.0 at a flow rate of 50-200cm/h, to obtain an elution fraction; 3) collecting the elution fraction of step 2), to obtain the solution containing recombinant human lactoferrin. 1) extracting recombinant human lactoferrin from transgenic rice seeds, to obtain crude extract containing recombinant human lactoferrin, 2) subjecting the crude extract containing recombinant human lactoferrin to cation exchange chromatography to perform primary purification, to obtain an elution fraction containing recombinant human lactoferrin; wherein: the cation exchange chromatography is performed on a weak cation exchange resin CM sepharose FF, the chromatography step comprises: 2A) equilibrating the chromatography column with 5-15 times column volume of buffer containing 10-25mM Tris, 10-25mM NaAC, 0-250mM NaCl, pH 6.0-7.5, at a flow rate of 50-200cm/h; 2B) using the crude extract of step 1) as a loading sample, wherein the sample having a conductance of 2-25ms/cm and a pH of 6.0-7.5; eluting impurities with an impurity-washing buffer, the impurity-washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 200-300mM NaCl, pH6.5-8.0, and the elution flow rate being 50-200cm/h; 2C) eluting the sample with a washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 400-650mM NaCl, pH 6.5-8.0 at a flow rate of 50-200cm/h, to obtain an elution fraction; the cation exchange chromatography is performed on a weak cation exchange resin CM sepharose FF, the chromatography step comprises: 2A) equilibrating the chromatography column with 5-15 times column volume of buffer containing 10-25mM Tris, 10-25mM NaAC, 0-250mM NaCl, pH 6.0-7.5, at a flow rate of 50-200cm/h; 2B) using the crude extract of step 1) as a loading sample, wherein the sample having a conductance of 2-25ms/cm and a pH of 6.0-7.5; eluting impurities with an impurity-washing buffer, the impurity-washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 200-300mM NaCl, pH6.5-8.0, and the elution flow rate being 50-200cm/h; 2C) eluting the sample with a washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 400-650mM NaCl, pH 6.5-8.0 at a flow rate of 50-200cm/h, to obtain an elution fraction; 2A) equilibrating the chromatography column with 5-15 times column volume of buffer containing 10-25mM Tris, 10-25mM NaAC, 0-250mM NaCl, pH 6.0-7.5, at a flow rate of 50-200cm/h; 2B) using the crude extract of step 1) as a loading sample, wherein the sample having a conductance of 2-25ms/cm and a pH of 6.0-7.5; eluting impurities with an impurity-washing buffer, the impurity-washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 200-300mM NaCl, pH6.5-8.0, and the elution flow rate being 50-200cm/h; 2C) eluting the sample with a washing buffer containing 3-10mM NaH 2 PO 4, 3-10mM Na 2 HPO 4, 400-650mM NaCl, pH 6.5-8.0 at a flow rate of 50-200cm/h, to obtain an elution fraction; 3) collecting the elution fraction of step 2), to obtain the solution containing recombinant human lactoferrin.