《This Is It》的詞曲作者是Michael Jackson，以下是歌曲的詞曲：
"This Is It"
Verse 1:
This is it, the moment we've all been waiting for
The king of pop, back on the scene
And it's time to dance, time to sing
This is it, the world is watching me
Chorus:
This is it, the time has come for me to show
What I've been through, what I've been through
This is it, the time has come for me to be
The best of me, the best of me
Verse 2:
I've been through it, I've been through pain and loss
But I've survived, I've survived the test
And now I'm here, singing my heart out
This is it, I'm giving it my all
Chorus:
This is it, the time has come for me to show
What I've been through, what I've been through
This is it, the time has come for me to be
The best of me, the best of me
Bridge:
Oh I know that I can do it, I'm feeling confident
No need to doubt, this is my time
So here I go, gonna take my chance
This is it, gonna make a change
Chorus:
This is it, the time has come for me to show
What I've been through, what I've been through
This is it, the time has come for me to be
The best of me, the best of me
Outro:
This is it, the moment we've all been waiting for"
以上就是《This Is It》的詞曲內容，是一首充滿熱情和動力的歌曲，展示了麥可·傑克遜的演唱風格。