The British Horseracing Authority is taking "extremely seriously" allegations made by former jockey Gay Kelleway.
Now a successful trainer, Kelleway, 53, who broke new ground for female riders, said she encountered serious harassment during her riding years, including an incident at Leicester racecourse involving a "senior jockey" when there were "stewards around".
She told the Daily Mirror: "I got harassed so much, people have no idea what sort of a tough time I had. It was horrible. I just wished they would leave me alone. All I wanted was to do my job to the best of my ability."
She added: "I was young then. I was a kid. I never said anything because no one believed you. 'You must have provoked them' - that's what you got."
Responding to the article, the BHA said in a statement on its Twitter page: "The BHA takes these allegations extremely seriously.
"We are working with all partners in our sport to ensure people are treated with respect. We are contacting the trainer concerned to seek further details."
A later statement issued on behalf of the BHA, the Professional Jockeys Association, the National Trainers Federation, the National Association of Stable Staff, the Racecourse Association and Racing Welfare said Kelleway has been offered "support and assistance".
The statement read: "The racing world is very concerned by the allegations that one of our leading female participants was sexually assaulted and harassed during her career as a jockey.
"There is no place for such behaviour in our sport. Respect for each other, for our colleagues and our officials is core to our values.
"We have policies in place across the sport to address concerns about bullying, harassment and inappropriate behaviour, but we are always working to improve the welfare of our participants. We want a culture where all our people are confident to report concerns.
"Anyone who feels they have been affected by unacceptable behaviour may contact the 24/7 confidential helpline run by Racing Welfare, the sport's own charitable body, which offers support and advice. Trained counsellors are on hand to answer calls.
"Racing Welfare will liaise with the sport's governing body, the British Horseracing Authority, and other authorities as appropriate.
"The bodies that represent professional jockeys, trainers, stablestaff and racecourses, support Racing Welfare's primary role for those who wish to get in touch in confidence, but will also support their members and staff if they ask for assistance in raising a concern.
"The BHA, as the governing body, is coordinating this response and will work with all partners in the sport and other relevant authorities to address any issues that arise from this case.
"The BHA has spoken to the trainer concerned to offer support and assistance."