Fly or take train to Barcelona from Avignon in France

The train -- flying makes zero sense for this trip. I am not even sure that there are any flights from Avignon to Barcelona so you would have to go to Marseille and then most likely take a one-stop flight to get to Barcelona. The train trip is only four hours. Look for trains from Avignon or from Nimes.

Train, no questions asked.

Cindy,

You may check train schedules on SNCF.com.

There are 2 train stations in Avignon; Avignon Centre is closest to the historic center (just outside the medieval wall) and Avignon TGV which is on the outskirts of the city. There is a TER train traveling to/from Avignon Centre to/from Avignon TGV (travel time 6 minutes)
Most long distance trains depart from the Avignon TGV station.

We took this route many years ago, but in reverse ( Barcelona >> Avignon), but we stayed overnight in Girona.
This was before the TGV train, so it took almost all day to travel from Girona to Avignon!

Enjoy your trip!

The SNCF site will show you that one high-speed train ex Avignon TGV station does not require changing trains and is at least an hour faster than the other trains of the day, which also require connections. Conventionally the SNCF tickets go on sale approximately three months in advance and will be cheapest at that point. Sometimes there are deals offered even earlier and you can get SNCF to put you on their notification list.
Avignon airport is small and offers little scheduled service. The nearest significant airport is Marseille and it has a late-afternoon flight to Barcelona lasting about an hour. But the local train from Avignon Central to the airport takes at least an hour and then there are all the two-hour hassles before take-off. In that time the fast train would have you across the Spanish border, and with a more comfortable ride.