The defending Olympic champion blitzed her rivals in last night's first round and it was more of the same again in the last 18 as she scored 407.25.
Closest rival Meaghan Benfeito from Canada was 47.35 behind, with 16-year-old Australian Brittany Broben third.
While the points from this morning do not carry through to the final, it is hard to see Chen, who won her third Olympic gold in the Synchronised 10m Platform last week, being caught.
Despite that, Chen said: 'It was so-so. There were some dives that were not perfect, some entries that were not perfect. It's encouraging me more. I'm taking my competition even more seriously.'
I didn't do as well as I wanted to but that's the nature of the Olympic Games, you never know what is going to happen.Paola Espinosa Sanchez
Benfeito, fourth at last year's World Championships in Shanghai, had to overcome some jitters in training this morning before producing a score of 359.90.
'This morning my training was awful so I didn't know what to expect,' she said.
'I think everyone can be on the podium because on the results of the semi-final we are very close to each other so it's going to be hard.'
Mexico's Paola Espinosa Sanchez was almost a major casualty as she only snuck through to the last 12 on her final dive.
'I didn't expect to get to the final so I am really happy,' the World Championships bronze medallist said.
'I didn't do as well as I wanted to but that's the nature of the Olympic Games, you never know what is going to happen.'