Disclosed is a non-natural ceramide compound effective for a sphingosine kinase activator, and thus useful for a skin disease treating agent. The sphingosine kinase activator enhances production of sphingosine-1-phosphate to show various physiological activities provided by sphingosine-1-phosphate. The physiological activities include the effects of: controlling multiplication and differentiation of keratinocytes, multiplication of fibroblasts and collagen synthesis, resulting in treatment of wounds, recovery of damaged skin functions in atopic dermatitis and psoriasis; inhibiting wrinkles and skin irritation caused by ultraviolet rays, followed by improvement of wrinkles and inhibition of skin aging; and reducing skin atrophy, which is a typical side effect of local application steroids. Therefore, the sphingosine kinase activator is useful for a skin disease treating agent for treating skin wounds, wrinkles, atopic dermatitis, eczema, psoriasis, or skin atrophy caused by side effects of local application steroids.