Most cruise lines do allow travelers to bring their portable oxygen concentrator. However, it is important that you let the cruise line know you will be traveling with oxygen ahead of time. Travelers may be required to fill out special needs forms. You will want to familiarize yourself with any rules of the cruise liner before boarding the ship. The cabins on cruise ships should have AC power wall outlets that can be used just like the power outlets in your home. Many cruise ships also have power outlets throughout the different areas of the ship so you can plug in your portable concentrator while you dine or while you enjoy other activities without draining the unit's battery. However, you are free to operate your portable oxygen concentrator on battery power throughout the ship.