He fared much better than teammate Gus Kenworthy, who failed to land any of his three runs and came in last.
Oystein Braaten of Norway claimed the gold medal of freestyle skiing men's slopestyle at PyeongChang Winter Olympic Games here on Sunday.
Braaten, one of the sport's most consistent skiers and a fine rail technician, has two Winter X Games golds in slopestyle.
"I didn't even know that was a televised moment at all", Kenworthy said.
With a score of 93.6, Goepper finished second in the USA men's free ski slopestyle.
Speaking after the final, Goepper said he changed his initial plan once the high quality of the field became evident.
The 21-year-old took a tumble in both runs, in what was his first showing in the Winter Olympics.
"Just being a part of a final like this was amazing.The level was so high, so numerous guys I have looked up to and inspired me every day to go out and ride". "There were some really good guys still to drop, so it was a nail-biting moment waiting at the bottom".
The event was ultra-competitive from start to finish - eight of the 12 qualifiers for the final scored more than 90 points.
Alex Beaulieu-Marchand of Canada took this year's bronze.
The 23-year-old said the Olympic final had drawn out the best performance of his career. He placed second in the same event this year.
Great Britain's James Woods came fourth, while Canadians Teal Harle and Evan McEachran ranked fifth and sixth respectively.
Braaten set his leading position with 95.00 points in the first run, an intact score throughout the competition.
Compatriot Izzy Atkin won bronze in the women's ski slopestyle on Saturday.