The court considered her absence as an attempt to escape although she would earlier assigned her lawyer to notify the court that she could not attend the hearing of the verdict because she developed sickness from the imbalance of fluids in the ears.
Yingluck s premiership was scuttled in 2014 by a court ruling over a technicality.
"We think that the defendant is hiding or has fled", a statement from a Supreme Court judge said.
He said the court would seek permission for an arrest warrant for the former prime minister, adding that verdict has been rescheduled to September 27. The sheer number demonstrated the military's desire to show their control of the situation, an image spoiled by Yingluck's non-attendance.
The Supreme Court on Friday issued an arrest warrant for Yingluck. However, her lawyer Norwait Lalaeng claimed he was unaware whether the former prime minister was still in Thailand.
"We have heard from officials that she hasn't showed up", Deputy Prime Minister Prawit Wongsuwan told reporters. In response, some 4,000 police were deployed around the area.
If her flight is confirmed, Yingluck will have joined her billionaire brother Thaksin in self-exile-a knock-out blow to the family and their political ambitions.
"What?" said a 75-year-0ld woman when told the court considered Yingluck to be a fugitive.
But she stepped out of his shadow, displaying a unexpected resilience as protesters besieged her home and opponents clobbered her with a raft of court cases. "She's a working woman and a strong woman".
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The court battle is the latest fight between the Shinawatra family, who are popular among the country's rural poor, and the royalist military elite. Yingluck has many homes and many cars. "She is now in Singapore, but I don't know how long she will stay there or where her next destination might be", one source told the German DPA agency, asking not to be named.
Yingluck, whose government was toppled by a 2014 coup, is accused of criminal negligence for disregarding advice that her rice price policy was flawed.
A former telecommunications tycoon, Thaksin has lived in self-exile to avoid a 2008 conviction for graft that he said was politically motivated.
But three years of repressive junta rule has successfully quashed any widespread opposition to the military for now.
Their Pheu Thai party has - under various different names - won every election since 2001.
A verdict had been expected Friday, in which Yingluck is facing charges of negligence linked to an ill-fated rice subsidy program that cost the state billions of dollars. It left Thailand with huge rice stockpiles and caused $8 billion in losses.
Yingluck said at the time of her overthrow said she had acted with integrity and honesty during her time in power.
"I think the designer of the program did not think carefully, did not understand the functioning of the rice market, particularly the world rice market", said Niphon Poapongsakorn from the Thailand Development Research Institute, who gave evidence at the trial.
"The government is anxious about the people".