The 26-year-old Czech international defender signed a four-year deal after completing a move from Paris St Germain for £2.8m which could eventually amount to around £3.26million.
Cech Sells Toon To Czech
Rozehnal: "I spoke a lot with Petr Cech and he told me it can be a big experience and a big chance for me at Newcastle.
"I am really happy because my dream has come true. I have always dreamt about this competition - for me, the Premier League is one of the best in the world.
"Now it is about work and about showing everybody I am in the right place.
"For me, it will be another big step. From the Czech Republic to Belgium, from Belgium to France and now from France to the Premier League - I am really excited because I will play against the best footballers in the world.
"Now I have to show my best, and I hope I will do that.
"I know the coach was interested in me when he was at Bolton and I am really happy he is still interested in me.
"It is really important that the coach believes in me and has given me my chance. Now it is up to me, if I work hard, to show him and my team-mates that I can get into the team.
"I am really happy that everything is done and now I am ready to prepare for next week."
Rozehnal began his career with Czech side Sigma Olomouc, then played for Belgian club FC Bruges before going to France.
Toon boss Sam Allardyce says Rozehnal as a key signing in rebuilding his much-maligned defence. He joins other signs this summer, Joey Barton and Mark Viduka.
Allardyce: "David is a hugely experienced centre-back and has played at a high level in Europe.
"He has played plenty of games for his country, and at 26 he is at the right age to learn and to adjust to playing here in the best league in the world.
"Hopefully, he can adjust as quickly as possible and we will try to make that easier for him.
"He is a very useful player indeed and a smashing fellow. He speaks English and four other languages. He is a very valuable addition to us.
"We will be looking to ease him into a role rather than throw him straight in at the deep end. But he is a very ambitious person and a good character too."
The Czech defender could make his first appearance for the Toon at Hartlepool United on July 17.