Prymnessus or Prymnessos (), or Prymnesus or Prymnesos (àÃÂÃÂüý÷ÃÂÿÃÂ), or Prymnesia (àÃÂàüý÷ÃÂïñ) was a town of ancient Phrygia. Its site is located near Sülün in Asiatic Turkey.
The town was inhabited during Roman and Byzantine times. It was the see of a Christian bishop. No longer the seat of a residential bishop, it remains a titular see of the Roman Catholic Church.
The martyr and saint Ariadne of Phrygia lived here according to her vita.