Objective:To understand the monkeypox knowledge awareness, risk perception and vaccination intention in men who have sex with men (MSM) in five cities in northeast China.Methods:A cross-sectional study was conducted by using electronic questionnaire in MSM selected by convenience sampling in five cities in northeast China (Shenyang, Panjin, Changchun, Harbin and Jiamusi) from June 28 to July 8, 2023 by local centers for disease control and prevention and MSM communities. The sample size was estimated to be 220. Information about their demographics, monkeypox-related knowledge awareness, perceived concern about epidemic risk perception, and monkeypox vaccination intention were collected. Logistic regression model was used to analyze related factors for MSM's monkeypox vaccination intention.Results:In 355 MSM, 63.9% (227/355) had monkeypox vaccination intentions, and 55.5% (197/355) had high awareness of monkeypox related knowledge with a mean knowledge awareness score of 3.7±1.5. MSM with education level of high-school and above (a OR=1.93, 95% CI:1.01-3.69), higher knowledge awareness score (a OR=1.19, 95% CI:1.02-1.40) and higher risk perception of monkeypox infection (a OR=1.82, 95% CI:1.15-2.88), were more willing to receive monkeypox vaccination. The main reasons for willingness to receive monkeypox vaccine were preventing monkeypox (86.3%, 196/227) and worrying about appearance being affected (62.1%, 141/227). The main reasons for unwillingness for the vaccination included concerns about vaccine safety (53.1%, 68/128), clinical progression of AIDS being affected (46.1%, 59/128) and efficacy of antiretroviral therapy being affected (44.5%, 57/128). Conclusions:The levels of knowledge awareness and vaccine intentions still need to be improved among MSM in five cities of northeast China. It is necessary to improve the awareness of monkeypox and intention of monkeypox vaccination, promote protected sex behavior and self-assessment of infection risk, reduce vaccine hesitancy and increase monkeypox vaccination intention in MSM in 5 cities in northeast China.