Ermengol IX (c. 1235 – 1243) was a medieval Catalonian nobleman. After his father's death in 1243, the eight-year-old boy succeeded as Count of Urgell. However, he, too died during the same year, situation in which he was the only Count of Urgell to die during his early years. The son of Ponce IV of Urgell and María Girón, he was buried in the Church of Santa Maria de Farfaña.