Members of Parliament from the Movement for Democratic Change (MDC) and their leader Nelson Chamisa heckled Mnangagwa when he started reading his speech before filing out and leaving the national assembly.
MDC members had been quoted by local newspapers on Tuesday saying they planned to embarrass Mnangagwa.
After leaving parliament, the MDC lawmakers broke into song denouncing the ruling ZANU-PF party.
But Mnangagwa, who has previously called for unity among the country’s political parties to help rebuild the shattered economy, said the elections were now in the past.
“The election period is decisively behind us. It is now time for us as members of parliament and political leaders to exert our efforts toward delivering promises we made to the electorate,” Mnangagwa said in his speech.