You need an ETA for Northern Mariana Islands if you have a Chinese passport

Travellers need a travel authorization to visit Northern Mariana Islands for Business or Tourism for a maximum of 14 days. The CNMI Economic Vitality & Security Travel Authorization Program (EVS-TAP) is an online application that determines the eligibility of visitors to enter Northern Mariana Islands. Once the application is approved, travellers receive their CNMI EVS-TAP confirmation electronically. Travellers must have a round‑trip ticket with a confirmed return date within 14 days. Otherwise, a paper or embassy visa is the only type of visa available to these travellers. The visa is typically a stamp or sticker added to the passport. Travellers must obtain this visa from a local embassy, consulate or visa center before travelling. Visit the government website to check other entry requirements.