Andronikos (Greek: Ἀνδρόνικος) was the metropolitan bishop of Sardis in 1250–60 and 1283–84 and involved in the ecclesiastical and political disputes of his time.
In 1253/4, along with George Kleidas, the Metropolitan of Cyzicus, he led an embassy on behalf of the Nicaean emperor John III Doukas Vatatzes (r. 1222–54) to Rome, to negotiate with Pope Innocent IV about a possible Union of the Churches.
As a result, in 1260 he was deposed and tonsured as a monk (with the name of Athanasios) at the Monastery of the Saviour at Selymbria by Joannicius, Metropolitan of Philadelphia.
Mired in dispute over the legitimacy of Gregory II's appointment, the synod achieved little, but one of his pupils denounced Andronikos for lese majeste.
Indeed, the Metropolitan of Larissa Nikandros is said to have mockingly removed his bishop's mitre and replaced it with a monk's cowl in front of the entire synod.