A fùxìng (compound surname) is a Chinese family name composed of two characters, such as Ouyang, Sima, or Shangguan. Unlike the much more common single-character surnames (e.g., Wáng, Lǐ), compound surnames are relatively rare today but historically significant—many originated from ancient noble titles, official posts, or regional names. The character fù means 'repeated', 'dual', or 'compound', while xìng means 'surname' or 'family name'; together, they literally denote a 'double-character surname'.

Compound surnames appear frequently in historical texts, classical literature, and among certain families preserving ancestral lineage. Though fewer than 1% of modern Han Chinese bear a fùxìng, they remain culturally prominent—think of famous figures like Ouyang Xiu (Song dynasty scholar) or Sima Qian (Han dynasty historian). When writing or pronouncing them, both characters must be treated as an inseparable unit: the full two-character name is the surname, and the given name follows afterward.