While Lumia 830 has been confirmed for many markets and should land in October in many of them, we didn’t hear much about Lumia 830 plans for China.
Now, the RM-984 variant of the device has passed certification on Tenaa, the Chinese equivalent of FCC. Usually, this means devices will get listed by retailers soon. On checking quickly, I couldn’t find it listed on JD or TMall yet, but expect it to happen soon.
You can read more about Lumia 830 at the dedicated page and discuss in Lumia 830 Forum.