Selling price managing system and method therefor

A selling price managing system for commodities which are ordered through a network, comprising:

• first storage means for storing the selling prices of the commodities;
• second storage means for storing the number of pieces of the commodities in stock;
• a price variation rule which determines a variation rule of the selling price on the basis of the number of pieces of each commodity in stock;
• and
• price varying means for referring to the number of pieces of each commodity in stock which is stored in said second storage means and the price variation rule to judge whether the variation of the selling price of the commodity is needed, and varying the selling price of the commodity stored in said first storage means if the variation of the selling price of the commodity is needed.