A British Airways airplane carrying the Queen and her husband Prince Philip arrived at Vilnius International Airport at 8:30 p.m. (1730 GMT), 10 minutes ahead of schedule.
Wearing a white coat, with black shoes and gloves but no hat, the queen disembarked and walked along a red carpet, past a Lithuanian guard of honour.
She and Prince Philip were welcomed to Lithuania, the first stop on a four-and-a-half day visit to all three Baltic states, by Prime Minister Gediminas Kirkilas, who presented the 80-year-old monarch with a bouquet of flowers.
Half a dozen other dignitaries, including the British ambassador to Vilnius, Colin Roberts, and Lithuania's ambassador to London, Vygaudas Usackas, were also on hand to greet the queen.
The welcome at the airport was swift, in the clear but chill autumn evening, before the royal couple were driven into Vilnius.
The official part of the royal visit will begin on Tuesday morning, when the Queen is scheduled to meet with President Valdas Adamkus.
After bilateral talks with Adamkus and an exchange of gifts, the Queen is to visit Antakalnis cemetery in Vilnius to honour Lithuanians who died fighting to reassert their country's independence from Moscow.
The three Baltic states of Lithuania, Latvia and Estonia were incorporated into the Soviet Union at the close of World War II and only regained independence in 1991, as the USSR disintegrated.
Construction workers scurried on Monday to put the finishing touches to City Hall Square, ahead of the first walkabout of the royal visit, which will take the Queen and Prince Philip to all three Baltic states in four days.
The royal couple will on Tuesday attend a reception hosted by the British ambassador. Among guests at the reception will be 10, 80-year-old, Lithuanians, representing all 10 Lithuanian counties.
Elizabeth II will later on Tuesday give a speech in the Lithuanian parliament and also visit Vilnius University. The first full day of the royal visit will conclude with a dinner hosted by President Adamkus and his wife Alma.
On Wednesday the royal couple will leave Vilnius for the Latvian capital, Riga.
The royal visit will end on Friday in Estonia, the northernmost of the Baltic states.
This year marks the 15th anniversary of the restoration of diplomatic ties between Britain and the Baltic states, which were independent between 1919 and 1940.
Adamkus, Latvian President Vaira Vike-Freiberga and then Estonian president Arnold Ruutel each met Queen Elizabeth during their respective official visits to Britain in July.
Ruutel was beaten in last month's race for the Estonian presidency by Toomas Hendrik Ilves.

Copyright AFP (Agence France-Presse), 2006