Bus connections from Porec to Ljubljana in Slovenia, trough out the year it is possible to travel by direct bus between the cities, travel time for the 160 km long bus routes is about 4 hours. Check the ICONs in the timetable below to see operational days and period of the bus. If you are doing a roundtrip you should consider buying a return ticket with the SAME bus company, as those tickets has a discount. Timetable for buses in the oppesite direction you can find here.
If you final destination is Ljubljana airport, you have frequent departures to the airport from the Ljubljana bus station, which is where the bus from Porec will drop you off.