莴苣缬草（学名：Valerianella locusta），又名野苣、羊莴苣，是败酱科新缬草属的一种双子叶一年生或二年生植物，原产于欧洲、北非及西亚。

莴苣缬草的叶为靠近地的基生莲座叶丛，叶为匙形，长达15.2厘米。其耐寒性很好，被列入USDA耐寒性第5类，在温带地区作为冬季绿色蔬菜种植。当气温变热时，会抽苔结子。 莴苣缬草生长在欧洲部分地区，非洲北部，亚洲西部。在欧洲和亚洲，莴苣缬草是一种耕地和闲置地上常见的野草。在北美洲，它们已经逸生到野外，在东部和西部沿海都已成为归化植物。

Valerianella locusta is a small dicot annual plant of the family Caprifoliaceae that is an edible leaf vegetable with a characteristic nutty flavor, dark green color, and soft texture, popularly served as salad greens. Common names include corn salad, common cornsalad, lamb's lettuce, mâche, fetticus, feldsalat, nut lettuce, field salad, and rapunzel. In restaurants that feature French cooking, it may be called doucette or raiponce, as an alternative to mâche, by which it is best known. In German-speaking Switzerland it is known as Nüsslisalat or Nüssler, terms that have been borrowed by the area's many English-speakers.