Sian Grigg, from Cardiff, has been nominated for an Academy Award for her work with DiCaprio on The Revenant.
He thanked Ms Grigg during his acceptance speech at the Golden Globes, where he won the best actor award for the film.
"My make-up artist, Sian Grigg, you are an unbelievable talent," he said.
Ms Grigg has worked with DiCaprio on several films including Titanic, Inception and The Great Gatsby.
"I had a lovely art teacher at Ysgol Gyfun Gymraeg Glantaf, Mr Anthony Evans," she told BBC Wales' Cymru Fyw  last week.
"He encouraged me and helped me get a place on the foundation course at Cardiff Art College."
She then specialised in make-up at London Fashion College before forging a career working on films including Saving Private Ryan, 28 Days Later, Ex-Machina and Suffragette.
But the make-up artist was keen to return to her home town, moving back to Cardiff six years ago.
"I noticed that I was always away on location so there was not much point staying in London.
"Although I've worked in many amazing countries, Wales will always be home. It's hard to beat Wales," she said.
Pembrokeshire-born actor Christian Bale has also been nominated for an Oscar in the best supporting actor category for his role The Big Short.

Lights first went off as Ramon Lobo, a pro-government lawmaker, defended the energy policies of President Nicolas Maduro, reports said.
Opposition MP Luis Florido quipped on Twitter: "The country's reality has hit them in the face."
The session was later suspended. Venezuela faces a severe electricity crisis and shortages are frequent.
Reports said other buildings in the same area of the capital, Caracas, were also hit by power cuts, on Wednesday afternoon.
Venezuela's National Assembly is controlled by the opposition.
Delsa Solorzano, an opposition MP, tweeted a video of the chamber in the dark.
MP Freddy Guevara, also from the opposition, said: "What a shame: the parliament session was interrupted because the energy went off. Right on the day we're discussing the energy sector law."
Oil-rich Venezuela is in the middle of a deep economic crisis caused by a drop in global oil prices. The country is suffering from a shortage of basic goods, food and electricity.
Earlier this year, the government introduced power rationing and a two-day working week for public sector workers as ways to tackle the crisis.
It said a major drought, which dramatically reduced water levels at its main hydroelectric dam, was to blame. But the opposition accused authorities of mismanagement.
Some of the measures have already been lifted.
A Welsh make-up artist described as a "genius" by actor Leonardo DiCaprio has been nominated for an Oscar.
[NEXT_CONCEPT]
A power cut left Venezuela's parliament in the dark as it discussed a law dedicated to the energy sector.