The present invention provides a cell carrier containing a nanofiber composed of water-insoluble polysaccharides, preferably chitin or chitosan nanofiber; a carrier capable of being a common carrier in various operations such as i) suspension culture, ii) differentiation induction, iii) transportation and preservation under non-freezing conditions, iv) transplantation, v) recovery of bioactive substance from culture supernatant and the like of adherent cells; and continuous performance of plural operations selected from i) suspension culture, ii) differentiation induction, iii) transportation and preservation under non-freezing conditions, iv) transplantation, and v) recovery of bioactive substance from culture supernatant of adherent cells by using the carrier.