Wrong. Though there are divergences, Chinese in mainland China use simplified Chinese characters (https://en.m.wikipedia.org/wiki/Simplified_Chinese_character...).
Kanji is more closely related to the traditional Chinese characters (https://en.wikipedia.org/wiki/Kanji#Local_developments_and_d...) than the mainland simplification.
>I would be surprised if you indeed learned the traditional characters while learning Japanese.
Kanji is closer related, or exactly the same as traditional Chinese characters (used in HK, Taiwan, etc.) than simplified.