Theodoros Alexis (; born 6 May 1975) is a Greek former professional footballer who played as a midfielder.
Alexis started at Attalos and in 1992 he moved to Apollon Athens. He had a fairly good presence at the club, emerging as one of the youngest scorers of the Greek championship, as scored his first goal at the age of 17.
On 7 July 1997, Alexis was transferred to AEK Athens alongside his teammate, Vangelis Kefalas. At AEK he played only 4 times for the championship as a substitute, without managing to gain the trust of the manager Dumitru Dumitriu. Thus, on 15 January 1998 he was loaned to Athinaikos. After his loan was expired he was released from AEK and on 3 August 1998 then returned to Apollon. After two seasons with the club he played for lower-division clubs, such as Akratitos, Panelefsiniakos and Marko before retiring in 2003.