Techniques are described for the extraction and purification of FSH and LH from human pituitary glands. The methodology uses acetone and alcohol for dehydration, extraction and precipitation of materials from both acetone preserved and fresh frozen glands. The processing involves the use of anion and cation exchange chromatography, adsorption techniques, and molecular sieve chromatography. Immunoaffinity extraction and purification of the gonadotropic hormones are also described. The specific activities of the LH preparations from acetone-preserved glands and from fresh frozen glands ranged from 11,200 to 12,640 IU/mg (68/40) and contained less than 0.2% TSH and FSH contamination. The yield varied from 9% to 18%. The specific activities of the FSH preparations from fresh frozen glands and from acetone preserved glands by affinity extraction (4990 and 4600 IU/mg 78/549) were higher than that from acetone preserved glands (3235 IU/mg). The LH and TSH contamination was less than 0.5%. The highest yield of FSH (34%) was obtained by affinity extraction. The preparations are of sufficient purity for use as immunogens and standards and for the preparation of radioligands to be used in specific and sensitive immunoassays.