The present invention involves a process for the manufacture of &agr;, &ohgr;-diiodoperfluoroalkanes of the formula I—(CF2CF2)n—I, wherein n is an integer between 2 and 6. The latter compounds are produced at relatively high conversions and under relatively mild reaction temperatures and pressures, compared to prior art processes, by the elimination of the gaseous byproduct perfluorocyclobutane throughout the process.