Transplanted olfactory ensheathing cells promote in juried spinal cord repair in the ratPart 1: Primary culture of olfactory ensheathing cells from neonatal ratolfactory bulbsObjective To culture and purify the olfactory ensheathing cells (OECs) in vitro, and to investigate the morphological features and the immunocytochemical properties of the cultured OECs. Methods The OECs were dissociated from the neonatal rat olfactory bulbs. The primarily cultured OECs were purified with the treatment of arabinoside cytosine (Ara-C), or immune-absorbed with anti-p75 antibodies, or a method based on the differing rates of attachment of the various harvested cell types. The purity of the OECs was evaluated according to the percentage of GFAP-immunostaining cells. The morphological changes of the OECs were observed under a phase contrast microscope at different culture time. Results The OECs display a very characteristic morphological appearance. Most of OECs are bipolar or tripolar with long and thin processes. In the unpurified group the rapidly proliferating fibroblasts were in the majority after 7 days in culture. Whereas in other three puritied groupes the purity of OECs was estimated to be over 75% after 14 days in culture. The OECs puritification by the method based on the differing rates of attachment of the various harvested cell types was a litter inefficient than those methods of using anti-p75 antibody or Ara-C. Conclusion The puritification is necessary in Primary culture of olfactory ensheathing cells from neonatal rat olfactory bulbs. The method of purification for OECs based on the differing rates of attachment of the various cell types is simple, inexpensive and practical in the research of the regeneration after spinal cord injury.