Mido, 24, has been granted a work permit and will go straight into the squad to face Fulham on Saturday.
Gareth Southgate moved to sign Mido after revealing how difficult he found it to play against the powerful frontman before hanging up his own boots last summer.
Mido, was also wanted by Sunderland and Birmingham City. He scored 19 goals in 61 appearances for Spurs before falling down the pecking order at White Hart Lane last season.
"He is someone I played against as a player and he always impressed me," Southgate told the club's official website.
"He gave me a hard game and he certainly has attributes I'd like to bring into the team to give us different options.
"When you've got one of the best crossers of the balls in the league in Stewart Downing, you want someone like Mido who can head the ball.
"You want a centre-forward to hold the ball up, to be a physical presence and to score goals. Mido brings all of those attributes."
Meanwhile, Southgate has hinted the arrival of Mido will not signal the end of his summer spending.
When asked if he was planning any more signings, he replied: "You never know.
"We're still a little bit short of numbers in certain areas of the field, but the chairman has shown me great support in the transfer market this summer so I'm grateful for what we've been able to do."