A fine cellulose fiber composite containing fine cellulose fibers having a carboxy group and an amine having an ethylene oxide/propylene oxide (EO/PO) copolymer moiety, the fine cellulose fibers being bound with the amine at the carboxy group to form a salt, wherein the fine cellulose fibers have a carboxy group content of 0.1 mmol/g or more, and wherein the molecular weight of the EO/PO copolymer moiety is from 700 to 10,000, and wherein a PO content ratio in the EO/PO copolymer moiety is from 1 to 70% by mol. The fine cellulose fiber composite of the present invention has high dispersibility in the resin and can exhibit an effect of increasing strength, so that the fine cellulose fiber composite is suitably as various fillers, and the like.