GameObjects in same size for any orientation

I am creating a game which supports both the orientation(i.e. Landscape & Portrait).

When I play game in portrait mode, all the game objects appear perfect. However, when while playing game or at the start of the game if I use Landscape orientation, all the game objects become small.

I need all objects appear same sized in almost both the orientation.

Can any one suggest a best way for this?

Thanks & Regards.