To enhance the expectation to a hit and continue the interest in game without giving a complicated sense to the player.

Display areas 11-16 constitute a first display area line 18 consisting of the display areas 11-13 of the lower stage and a second display area line 19 consisting of the display areas 14-16 of the upper stage. The display area line for variably displaying symbols is determined by lottery from the display area lines 18 and 19 is determined by lottery, and the symbols of the display areas 11-16 are variably displayed on the basis of the lottery result. When only the first display area line 18 is variably displayed, the symbols of the display areas 11-13 are variably displayed. When the first and second display area lines 18 and 19 are variably displayed, the symbols of the display areas 14-16 are variably displayed after the symbols of the display areas 11-13 are stopped and displayed. At this time, the display areas and symbols belonging to the display area line for variably displaying symbols are extensively displayed.