The present invention discloses a planting method for selenium-enriched pitaya. The method comprises: erecting a plurality of hollow columns with both ends open in a field, and then planting three pitaya seedlings around each column, wherein the distance between a root of each pitaya seedling and the column is 5-8 cm; and by taking the column as a center, separately digging a first ring-shaped pit, a second ring-shaped pit and a third ring-shaped pit, then applying organic selenium fertilizer in the first ring-shaped pit, applying a phosphate fertilizer in the second ring-shaped pit, and applying quicklime in the third ring-shaped pit. The pitaya produced by the method provided by the present invention has a high selenium content and can fully meet the demand of people on selenium, and the pitaya tree in the method has a high selenium absorption rate with less wasted selenium.