I want to show the more item link with image in single category item list page. Right now I am seeing the text link for more items option. I am a newbie for K2 component.

Thanks in advance

You can override K2's templates (category_item.php) and alter the read more button.
More on overrides can be found here: getk2.org/documentation/tutorials/174-templating-with-k2-and-the-concepts-of-sub-templates