In the 'Attack on Titan' universe, there's no explicit confirmation about Mikasa getting married. However, in the manga's final chapter, there is an interesting twist when she is seen under a tree by a grave, which is hinted to be Eren's, with a child running around.
This has led some fans to speculate that she may have settled down after Eren's death. Yet, the child's identity and whether Mikasa married remains uncertain, leaving this an open-ended question.