Melanie Wade wowed judges with a classic Derby Day black and white outfit that won her the lady of the day award.

The Horsham maternal and child health nurse has been on a roll this year, winning similar awards at two other Victorian country races and is set to attend Warrnambool's Ladies and Tradies Day on Friday.

"It's good fun to dress up, it's a nice change from being a mum and a maternal and child health nurse," Ms Wade said.

"You don't do it for the prizes, it's more about catching up with other people and the fun."

Her winning top and skirt was a By Johnny design, while her millinery was from Melbourne-based Hatricks by Michelle.

"It was a well-rounded outfit," Ms Wade said.

While some dressed to the nines, others took a different approach, appearing in costumes and casual wear.

"One girl had gumboots with horses, there were hen's days there dressed up as Disney characters, it's not all about fashion. It's a great day out to celebrate, let your hair down," Ms Wade said.

Mortlake Racing Club president Jason Hughes said the day was a success for the club, and was likely attended by at least 2500 people.

"Many of us are saying it has to be a record for here," Mr Hughes said.

"The club is rapt with the day, and I think our event is becoming synonyms and renowned with a really good day out."

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