Various 14-fluorinated anthracyclines (3a, 3b, 4, 24a, 26a, 24b, and 26b) were synthesized and subjected to in vitro cytotoxicity and in vivo antitumor activity assay against P388 murine leukemia. At first, 14-fluoro-4-demethoxydaunorubicin (3a), 14-fluorodaunorubicin (3b), and 14,14-difluoro-4-demethoxydaunorubicin (4) were synthesized by employing glycosylation of the corresponding aglycones (9a, 9b, and 18) with 3-N-trifluoroacetyl-1,4-bis(O-p-nitrobenzoyl)daunosamine (10) in the presence of TMSOTf followed by deprotection. Syntheses of the 14-fluoroanthracyclinones (9a and 9b) and 14,14-difluoroanthracyclinone (18) were achieved by featuring the substitution reaction of the 14-bromo-7-deoxyanthracyclinone (6a and 6b) with a combination of Bu_4N・F and TsOH and the Reformatsky reaction of the siloxyaldehyde (14) with ethyl bromodifluoroacetate as key steps. These compounds (3a, 3b, and 4) showed prominent cytotoxicity in P388 in vitro test. Among 3a, 3b, and 4, excellent in vivo antitumor activity against P388 murine leukemia was observed for 3a and 3b. Thus, 14-fluorodaunorubicin congeners (24a, 26a, 24b, and 26b), in which the L-daunosamine residue was replaced with 2-deoxy-D-ribose and 2-deoxy-L-fucose, were synthesized by using the same glycosylation reaction of aglycones (9a and 9b) with 1,3,4-tri-O-acetyl-2-deoxy-D-ribopyranose (21) and 1,3,4-tri-O-acety1-2-deoxy-L-fucopyranose (22). Although fairly weak cytotoxicity against P388 murine leukemia was only observed for 24a and 24b, 26a and 26b exhibited prominent cytotoxicity. The 14-fluorodaunorubicins (26a and 26b) were found to show highly effective T/C values in P388 in vivo assay.