The success of Oedipus rex as one of the great tragedians is largely due to the brilliant interplay of dramatic irony.Sophocles creats verious situations in which dramatic , verbal , and situational irony play key roles in the downfalll of Oedipus.Mostly, its dramatic Irony that plays a vital role in the fortune of Oedipus.                                                                                                                                       "An expression or utternce marked by a deliberate contrast bytheway apparent and intend meaning"                                                                                                                                                                                                Its not only used in tragedies but also in comedies.The use of irony adds to complexity of a play.It arouses the interest of the audience because they know the truth, and eagerly watch how a specific character , especailly the protagonist act and reacts in a particular situation.                                                                                                           

Irony involves differences between appearance and reality , expectations and result , or meaning and intention.Being ignorant of his fate or circumstances , the character tries to get rid of the trouble,but In Oedipus rex there are several instance of dramatic irony.Oedipus' speech in the initial part of the play demanding the people to reveal the murderer is an important instance of dramatic irony.The audience knows that Oedipus himself who is the killer of king Loius.Oedipus doesn't realise that in cursing Loiu's murderer to live in wretchedness he is curssing himself :he says

                                                                                                                                                               " Now my curse on the murerer whoever he is a lone man unknown in his crime or one among many....."                                                     

Another noticeable point of irony in the play grows from Creon , Oedipus brother-in-law early Oedipus charges creon and Teriseas with treason , wherease the audience knows that Creon has one third share in the state and has no interest in king ship.

Situational irony:

                                 In this play, the fact taht Oedipus is chief detective in the search of the culprit , who turns out to be Oedipus himself is , situational irony.

Verbal irony:

                      The speakers knowingly use ironic language .Teriseas uses verbal irony when Oedipus taunt him for his blindness.