Defense attorney Hal Haddon had argued that the law, when applied in combination with another law, violated Bryant's right to equal protection under the law.
The rape-shield law, which has withstood other challenges since it was enacted in the mid 1970s, generally bars defense attorneys from using information about the sexual history of alleged assault victims, unless a judge determines the information is relevant.
Haddon had argued that under another state law, a defendant's sexual history is presumed to be relevant and is admissible at trial.
State District Judge Terry Ruckriegle said Bryant's sexual history will not be brought up in court, making that argument irrelevant.
He also noted that numerous witnesses have testified behind closed doors about the consensual sexual activities of the alleged victim before her encounter with Bryant last summer, ensuring that the defense has a chance to introduce that information as evidence. More witnesses are expected to testify on that issue later this month.
Haddon did not immediately return a call for comment.
Bryant, 25, has pleaded not guilty to felony sexual assault. He has said he had consensual sex with a 19-year-old employee of the Vail-area resort where he stayed June 30.
If convicted, he faces four years to life in prison or 20 years to life on probation, and a fine up to $750,000.