Waleran (or Walram) I (died 1082), called Udon, was the count of Arlon from AD 1052 and Limburg from 1065. He was the son of Waleran, Count of Arlon. He was also the advocate of the abbey of Sint-Truiden.
The origins of his family are poorly known, he appears to have been a member of a collateral branch of the house of Ardennes, then ruling in Upper Lorraine. He may instead have been maternally related to that house. His mother may have been Adela, daughter of Duke Theodoric I.
He inherited Arlon together with his brother Fulk, who died in 1078, leaving him sole count. Waleran married Jutta, daughter of Frederick, Duke of Lower Lorraine. This marriage gave him the county of the Len (or Lengau), a district around Liège. Waleran constructed a castle in his new territory: the Lenburg, whence Limburg. Waleran made this castle his seat and he is known as the first count of Limburg. His son, Henry, inherited his counties on his death.