The Pole beat fellow favourite Espen Tveit of Norway by two seconds to secure the first gold of the championships in snowy Zakopane, with Kazakh skater Maxim Baklashkin claiming bronze.
"I am preparing for the European and World Championships, so for me it was quite a good race," Szymanski said.
In the only other medal race on the opening day of action, Martina Sabilkova of the Czech Republic cruised to victory in the women's 3,000m.
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Poland finish on high
04/01/2013 AT 01:29
The double Olympic champion won with a huge 15-second advantage over her nearest rival Luiza Zlotkowska, who took silver.
"Martina showed great class today," Pole Zlotkowska said. "It was really hard to compete against her. What's more, the snow caused some minor disturbances.
"I'm really happy with my silver nevertheless, all the more so with Janek winning gold earlier on today."
Norway's Marit Fjellanger picked up bronze in the final race of the day.
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World University Championships
Szymanski makes it three golds in Zakopane
04/01/2013 AT 01:24