In the year 2007 starts the search for the new Miss to represent the country in the maximum contest of the beauty; a young woman of 21 years with her green eyes and his style enveloped the jury when you convert to the queen in Venezuela.
Dayana, becomes the model since the age of 15, signing with prestigious agencies such as the Trump Model Managent and Elite, parading in walkways of New York, Germany, Italy, France, Athens and Spain for designers of the stature of Roberto Cavalli and Versace.
To have enough experience and preparation decides to enter in the 2007 to Miss Venezuela, representing the state of Amazonas. The 13 of September of that year, starts the gala event with the animation Maite Delgado and Daniel Sarcos, under a luxurious technology deployment and presentations of national and international artists.
After the customary round of questions that is reduced to 5 candidates, come to give the results and Ly Jonaitis, Miss Venezuela 2006, crown to Mendoza as the winner in full Polyhedron of Caracas; what she was not expected was the sudden emergence of individual who stepped onto the stage and stole the jewel by placing it on his head, he was able to know they were identified subsequently as John Chambers and its secuas Yendrick Sánchez; finally it was returned the crown to Dayana Mendoza.
A 14 July 2008, Venezuelan participates in the festival and in the rounds of questions and answers which is the difference between men and women, to what she said: «Men, think that the fastest and easiest way to go to a point is to go right, while the woman knows that the more fall going to point is to follow the curves» said.
Gets the title of Miss Universe 2008, in Nha Trang, Vietnam, a great victory without a doubt to the country, celebrated with a tiara of $120,000 more cash prizes; the Venezuelan decides to travel the world as several cities in the United States, Vietnam, Indonesia, Jakarta, Borobudur, Bali, Singapore, Argentina, Bahamas, Bolivia, Brazil, El Salvador, France, Puerto Rico, Czech Republic, Dominican Republic, Russia, Romania, Ukraine visiting charitable foundations, giving conferences humanitarian to raise funds and promote the fight against HIV.
Made a controversial visit to the bay in 2009 of Guantanamo commenting: «I did not want to leave and it was a lot of fun, we visited the fields and the detainees, seeing their cells, showers and watching movies, art classes, everything was very interesting».
These reviews led to a negative response massive of internet through photos, blogs and comments on social networks, so that the Miss Universe Organization issued a statement to support.
As a result of his reign were opened more doors in the middle, taking occurrences in commercials, television programs and interviews in the media until the present.