Itir Esen, 18, was crowned Thursday, but a few hours later she lost the title after it emerged she had tweeted about last year's failed coup in Turkey. In the tweet, she said her period had begun, "representing the martyrs blood."
The tweet has since been deleted, but there are screen grabs available.
"To celebrate July 15 Martyr's Day, I began the morning by getting my period. I am celebrating the day by bleeding representing the martyrs blood," the tweet read.
Esen tweeted on the anniversary of last year's coup attempt
in which around 250 people died.
"We announce with regret that the tweet was indeed sent out by Itir Esen," Can Sandikcioglu, president of the Miss Turkey Organization, said on the contest's website.
"It is not possible for the Miss Turkey Organization, which aims to introduce and support Turkey in the world, to accept such a post."
On her Instagram account
Esen said her tweet was not related to "July 15 or our national values" and apologized for the "misunderstanding."
"I made this post with innocence during a sensitive time without thinking. As any one who feels like a victim during their menstruation, it does not contain any meaning other than 'it is July 15 and this is my situation right now,' " she wrote on Instagram.
"I just want to say this: as an 18-year-old girl, I had no political agenda when I posted," she said.
Following the decision, runner-up Asli Sumen was crowned Miss Turkey. She will now represent the country in the Miss World contest in China in November.
Turkish President Recep Tayyip Erdogan has cracked down on opposition since the failed coup, firing thousands of civil servants
and incarcerating journalists and opposition politicians. He then won a referendum that strengthened his powers.