The calculated distance (air line) between Port-au-Prince and Port-de-Paix is approximately 102 miles respectively 164 kilometers.
By car or train, the actual journey to Port-de-Paix is certainly longer, as only the direct route (as the crow flies) between Port-au-Prince and Port-de-Paix has been calculated here.
Air line (approximately)
164 kilometers
88 nautical miles