A record 150 horses are expected to be presented at the show, the head of the Polish Jockey Club, Tomasz Chalimoniuk, said in an interview with Polish Radio.
He told the Polish public broadcaster that over half the horses at the show came from private breeders.
According to Chalimoniuk, "this proves that the industry is developing."
The highlight of the event is the prestigious Pride of Poland thoroughbred auction, which draws buyers from around the world, and which is set to take place on Sunday. Sixteen horses are planned to go on sale then.
Chalimoniuk said he had never seen "so much interest" in the auction.
"I wonder if this is because of the pandemic that people missed such events so much," he added.
Last year, 10 horses, bred at sites including the famed state-run stud farm in Janów Podlaski, were sold at the auction, fetching a combined EUR 1.59 million.
In 2019, 14 horses were auctioned off, fetching a combined EUR 1.39 million.
A record EUR 1.4 million was paid in 2015 for a 10-year-old mare named Pepita, with the auction bringing in a combined EUR 4 million.
The 43rd annual Polish National Arabian Horse Show runs until August 16.