Lennon developed through the England junior setups and was the youngest player to appear in the Premiership when he made his Leeds debut at White Hart Lane aged just 16years and 129 days.
Walcott, 17, has not played first-team football since his £12m move from Southampton in January but is regarded as one of the hottest talents in the game and Eriksson has decided to include him in his squad.
Meanwhile, former Leeds keeper Scott Carson is on the stand-by list along with Jermaine Defoe and Andy Johnson.
Sven-Goran Eriksson's provisional squad for the World Cup finals in Germany:
Robinson (Tottenham), James (Manchester City), Green (Norwich), G Neville (Manchester United), R Ferdinand (Manchester United), Terry (Chelsea), A Cole (Arsenal), Campbell (Arsenal), Carragher (Liverpool), Bridge (Chelsea), Beckham (Real Madrid), Carrick (Tottenham), Lampard (Chelsea), Gerrard (Liverpool), Hargreaves (Bayern Munich), Jenas (Totenham), Downing (Middlesbrough), J Cole (Chelsea), Lennon (Tottenham), Rooney (Manchester United), Owen (Newcastle), Crouch (Liverpool), Walcott (Arsenal).
Standby:
Carson (Liverpool), Young (Charlton), Reo-Coker (West Ham), Defoe (Tottenham), Johnson (Crystal Palace).