After nobody was arrested on the opening day, the 10 people were arrested for a variety of offences including possession of drugs and being drunk and disorderly.
About 65,000 people are expected at Ascot Racecourse today, which is Ladies' Day.
Supt Steve Hockin, silver commander for the event, said: “Despite a small handful of arrests, yesterday was yet another enjoyable day for the majority of race-goers.
“Today is going to be even busier with crowds expected to exceed 65,000.
“Given the warm weather, I would like to remind race-goers to keep hydrated and to drink in moderation and sensibly. People should also keep their belongings safely with them at all times.”