The 27-year-old, who was 27th after the opening run, was caught out by one of the gates during his second run, leaving himself 17th in the final standings, just over four seconds off the pace of gold medallist Mario Matt.
Ryding told BBC Sport: "I knew all about it. I knew what to do but I got kicked out. It's frustrating because if I hadn't made that mistake I could have done well.
"I'll be kicking myself for the rest of my life. The first run I skied cautiously on the top because it was really bumpy but I was able to charge a bit lower down and finished 27th and stayed 27th.
"I'm still getting better and I'm sure I could have a better result today, but still, that's life."
Austrian Marcel Hirscher finished second, while Norwegian teenager Henrik Kristofferson claimed the bronze.