Messi is playing in his 5th World Cup with Argentina at the 2026 tournament. He previously appeared in 2006, 2010, 2014, 2018, and 2022, so this is his fifth overall appearance.

Quick context

  • 2006: first World Cup.
  • 2010: second.
  • 2014: third.
  • 2018: fourth.
  • 2022: fifth.
  • 2026: sixth overall tournament if you count his current appearance in 2026, but fifth before this one.

In plain English

If you mean “How many World Cups has Messi played in total?”, the answer is 6 including 2026.
If you mean “Which World Cup is this in his career counting only past tournaments?”, it’s his 5th.