Provided are a fluorous-tag-introduced fluoroamine of a general formula (I), its production method, a method of fluorination of a substrate having functional group containing oxygen with the fluoroamine serving as a fluorinating agent, and a method of recovering a fluorous-tag-introduced amide after the fluorination. The fluoroamine and its production method, as well as the fluorination method with the fluoroamine and the method of recovery of a fluorous-tag-introduced amide are ecological and advantageous in industrial use, as the load for separating and collecting the product after the fluorination with the fluoroamine serving as a fluorinating agent is small. ##STR00001## (In the formula, R.sub.0 is an alkyl group or an aryl group having substituent(s) of Rf--(CH.sub.2).sub.m--; Rf is a perfluoroalkyl group; m is from 0 to 2; R.sub.1 and R.sub.2 each are an alkyl group or an aryl group.)