A fluorine-containing vitamin D2 derivative represented by the following formula
wherein R1 represents a methyl or trifluoromethyl group, and R2 represents a trifluoromethyl group when R1 is a methyl group, and a hydrogen atom or a methyl group when R1 is a trifluoromethyl group. This compound is useful for the prevention or treatment of caloium pathobolism or osteoporoeis.
A fluorine-containing vitamin D.sub.2 derivative represented by the following formula ##STR1## wherein R.sup.1 represents a methyl or trifluoromethyl group, and R.sup.2 represents a trifluoromethyl group when R.sup.1 is a methyl group, and a hydrogen atom or a methyl group when R.sup.1 is a trifluoromethyl group. This compound is useful for the prevention or treatment of calcium pathobolism or osteoporosis.