Generally, yes, it's best to peel parsnips before roasting. If the parsnips have thick or tough skin or if they are not fresh and the skin looks aged or discolored, it's a good idea to peel them. This can help improve their overall texture and taste. If the parsnips are fresh, young, and have smooth, tender skin, you can roast them without peeling. Plus, leaving the skin on can be more convenient and reduce food waste. Whether you peel the parsnips or not, it's essential to thoroughly scrub them under running water before use to remove any dirt and debris.