This invention discloses 2-methylene-(17Z)-17(20)-dehydro-19,21-dinor-vitamin D analogs, and specifically 2-methylene-(17Z)-17(20)-dehydro-19,21-dinor-1&alpha；, 25-dihydroxyvitamin D3, and pharmaceutical uses therefor. This compound exhibits relatively high transcription activity as well as pronounced activity in arresting the proliferation of undifferentiated cells and inducing their differentiation to the monocyte thus evidencing use as an anti-cancer agent and for the treatment of skin diseases such as psoriasis as well as skin conditions such as wrinkles, slack skin, dry skin and insufficient sebum secretion. This compound also has significant calcemic activity in vivo having about the same bone calcium mobilization activity and intestinal calcium transport activity as the native hormone 1&alpha；,25-dihydroxyvitamin D3, and therefore may be used to treat autoimmune disorders or inflammatory diseases in humans as well as renal osteodystrophy. This compound may also be used for the treatment or prevention of obesity.
