Peel papaya. Cut into half lengthwise. Remove seeds with a spoon.
Using a mandolin, slice papaya cross wise into thin slices about 1/8th of an inch thick.
Place sliced papaya in a large bowl. Sprinkle salt all over the papaya. Mix well and set aside for 15 minutes.
Place red chili floret in a bowl of cold water.
In the meantime, combine rice vinegar and sugar in a small saucepan over low heat. Stir until sugar has dissolved. Turn off stove and allow it to cool.
Washed and drain papaya slices twice. Transfer to a sterilized jar together with the red chili.
Pour vinegar mixture into the jar to completely cover the papaya slices. Screw on the lid.
Pickled papaya may be eaten after 2 hours.