Yes you can. By default, Zoho Invoice will not display a discount column when you create an invoice in the item grid section. If you provide specific discounts to your customers, you can customize it from the Settings page:

• Navigate to the Settings tab.
• Click on General Preferences under Preferences
• In the Discount section, click Yes.
• Specify a title for the discount column in the Show Discount As text box. By default, the title of the column would be Discount(%). Edit this title as relevant to your business.
• Click the Save button.