It is very likely there will not be any staining if you wipe the coffee immediately when it is spilled on wood. However, if the coffee sets in the wood, it may leave a tough stain to remove. Fortunately, most coffee stains can be successfully removed with common household items without using harsh chemicals on wood. Applying distilled white vinegar to the stain, for instance, will dissolve the coffee stain without damaging the wood.
Instructions

1. Professional cleaning services providers suggest using the following items: paper towels, mild liquid detergent, distilled white vinegar, clean cloth, and wood polish or wax.
2. Slightly dampen a stack of paper towels with water and add ½ teaspoon of mild detergent to the towels. You can use liquid soap instead of detergent as well.
3. Use the towels with the solution to wipe away as much of the coffee stain as you can, and then dry the area with a new application of paper towels.
4. Apply 1 teaspoon of distilled white vinegar to the stained area and let it sit for two minutes. Use clean paper towels to blot up the vinegar and dissolved coffee. Allow the wood to air dry completely.
5. Restore the natural shine of the wood by polishing it with a wood polish or wax paste. Apply 1 teaspoon of wood polish or the equivalent amount of a wax paste to a clean cloth and start rubbing the wood using circular motions as advised by professional cleaning services providers. Wait for the wax or polish to dry, then wipe with another clean cloth to shine.