The Irish are joint top of the group with nine points from their opening four games. Italy, Serbia and Slovenia also have nine points each.
"We are totally focused on Lithuania. We had a very good performance against them in Waterford earlier this month and we are looking for a similar performance and a similar result in Vilnius," said King.
"This is a hugely important game for us. We want to stay in the hunt for qualification and 12 points from the first 15 available would be a super start. This particular Irish team has a clear focus on what they want, they are together and determined to achieve it.
“The dressing room was full of disappointment after the 1-0 defeat in Italy. This stemmed from the fact that they had competed at a very high level and deserved something from the game. The only thing missing was goals. The team competed very well and limited them to just one shot on target while creating several chances ourselves.
“The players have set a high standard that they want to maintain it. The next test is winning in Lithuania.
"Unusually, there has not been many changes to the squad over the first four games. This consistency, together with winning, has helped to build a momentum, develop an understanding and build a strong team morale – all of which can be vital to success.
Using the same squad, the u21's will travel home to play a friendly game against Norway on November 17 in the RSC, Waterford (7.45pm).
King added: "Norway always prove an attraction and are a very difficult opponent, but at this moment the only focus is Lithuania. All our concentration and effort will go into trying to beat them in Vilnius and come back to the RSC with 12 out of 15 points. It’s a difficult task, but one this team are determined to succeed in.”
REPUBLIC OF IRELAND U21 SQUAD:
Daniel Rogers (Aberdeen - on loan at Falkirk)
Eric Grimes (Leeds United)
Sean Long (Reading - on loan at Luton Town)
Jack Connors (Dagenham & Redbridge)
Glen Rea (Brighton & Hove Albion - on loan at Southend United)
Darragh Lenihan (Blackburn Rovers)
Alan Browne (Preston North End)
Callum O’Dowda (Oxford United)
Josh Cullen (West Ham United)
Conor Wilkinson (Bolton Wanderers - on loan at Barnsley)
Jack Byrne (Manchester City - on loan at Cambuur)
Sean Kavanagh (Fulham)
Reece Grego-Cox (QPR)
Dylan Connolly (Ipswich Town)
Shane Griffin (Reading)
Henry Charsley (Everton)
Sean Hoare (St Patrick's Athletic)
Sean Maguire (Dundalk)
Lee Desmond (St Patrick's Athletic)
Kenneth McEvoy (Tottenham Hotspur)
Sam Byrne (Everton)
FIXTURES
Friday, November 13
UEFA U21 Championships Qualifying Round Group 2
Lithuania v Republic of Ireland, LFF Stadionas, Vilnius (KO 4.30pm Irish Time)
Tuesday, November 17
U21 International Friendly
Republic of Ireland v Norway, RSC, Waterford (KO 7.45pm)