The police fired water cannons, tear gas and stun grenades in a crackdown on protests.
The streets in the capital and other cities were quiet after violence on Sunday night, when riot police used force to disperse thousands of protesters who had gathered to denounce what they said was an electoral farce.
Referring to the crowds of people chanting her name, she said last night: 'I believe my eyes, and I see that the majority is with us'.
A government official claimed that no protesters had been injured.
Polish Prime Minister Mateusz Morawiecki called on European Union's leaders to convene an extraordinary summit to discuss Belarus, saying that the 27-member bloc should support the democratic aspirations of people in Belarus.
"From Poland, Great Britain and the Czech Republic, they controlled out, forgive me, sheep", he said.
Before the result was announced, Lukashenko said he did not expect foreign countries to recognize it.
Prominent rights group Viasna said Monday that a protester had been killed in the crackdown after suffering a traumatic head injury when he was hit by a police vehicle.
Belarus' EU and North Atlantic Treaty Organisation neighbours, Poland and Lithuania, also issued strong rebukes.
On July 16, a statement from the Ministry of Foreign Affairs said: "Estonia continues to express concern over the restrictions on peaceful gatherings and freedom of speech ahead of the upcoming presidential elections in Belarus".
With his main rivals either jailed or barred from running, Mr Lukashenko, 65, faced four other candidates including 37-year-old Mrs Tsikhanouskaya, the wife of an imprisoned YouTube blogger, who emerged as an unlikely face of the Belarusian protests.
The former culture and foreign affairs minister added: "Recent "so-called" elections in Belarus were much more to [Lukashenko] than just remaining in power". The campaign has generated the country's biggest opposition protests in years.
The administration has also nominated career diplomat Julie Fisher as ambassador to Belarus.
On the eve of the election Ms Tikhanovskaya's team said her campaign manager had been arrested and would not be released until Monday.
Belarus, which has a population of 9.5 million, has reported nearly 70,000 cases and almost 600 deaths.
Moscow has rejected the charges. He was followed by Russian President Vladimir Putin, the president of Kazakhstan, Kassym-Jomart Tokayev, and the leader of Azerbaijan, Ilkham Aliyev. The military was patrolling highways leading into the nation's capital.
"Lukashenko's victory will bring him no relief, it will only exacerbate both domestic and external problems of Belarus that will snowball", said Artyom Shraibman, an independent political analyst based in Minsk.