Ealhstan was a medieval Bishop of Sherborne. Ealhstan was consecrated between 816 and 825. He died in 867. According to the Anglo-Saxon Chronicle, he died in 867 after holding office for fifty years. However, a forged charter (S 283) of 824 appears to copy a genuine witness list of the mid-820s, and this describes Ealhstan as "electus in episcopatum Scireburnensis æcclesiæ", implying that he was not appointed until 824. This would be consistent with the absence of a bishop of Sherborne from records of the Council of Clofesho of 824.