Scallion oil noodles are tossed in a fragrant scallion oil sauce with soy sauce, garlic, and sometimes vinegar or sesame oil. Scallion oil noodles usually use thin wheat noodles or rice noodles for its base, and focus on fresh ingredients and delicate flavors. Scallion oil noodles are often enjoyed as a light and flavorful meal, particularly in the summer months, and are a popular choice for picnics and outdoor gatherings in Jiangsu and Shanghai.

Scallion oil mixed noodles originated in Shanghai, and its history can be traced back to the early 20th century. At that time, Shanghai's culinary culture was gradually prospering, and noodles, as the staple food for three meals a day, began to appear in various forms. A chef named Zhang, while making noodles for guests, tried adding cooked scallion oil and various seasonings to enhance the taste and texture of the noodles. The guests greatly appreciated it after tasting, and this scallion oil mixed noodles gradually spread and became one of Shanghai's characteristic cuisines.