Excitement has been building for months among the throngs of pilgrims from across the country expected to join the colourful celebration of Myanmar's ethnic diversity in the commercial capital.
The pope will wind through the crowds in a white 'popemobile' to greet his followers at close-quarters before conducting a ceremony due to start at 08:30 local time (02:00 GMT) on the third day of his visit.
The trip has so far been more political than religious.
It comes as the country feels under siege from the international community over the plight of its Rohingya Muslim community, who are shunned by many of the majority-Buddhist population.
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The pope avoided mentioning the crisis -- or the Rohingya -- directly at his only public speech so far in the country's capital on Tuesday, where he took the stage with Suu Kyi.
He called simply for "respect for rights and justice" while Suu Kyi stated that Myanmar's aims were "protecting rights, fostering tolerance, ensuring security for all."
The army has justified the campaign as a proportionate retaliation for attacks by hardline Rohingya militants in August.
But the UN and the US have labelled it ethnic cleansing and rights groups accuse the military of crimes against humanity with refugees recounting consistent reports of murder, rape and arson.
This is the first ever papal visit to the country although there have been Catholics in Myanmar for over 500 years.
In the last three years, the Vatican has canonised Myanmar's first saint and named its first cardinal before full diplomatic ties were established in May this year.