Suicide is a serious and preventable public health issue. This study aimed to identify the prevalence and associated factors of suicidal ideation (SI) among high school students. This cross-sectional study was conducted among 1,270 high school students. The Global School Student Health Survey (GSHS) questionnaire examined SI and related factors. The participant was identified as having SI by the question, “During the past 12 months, did you ever seriously consider suicide ideation?”. Overall, 16.9% of the participants reported having SI during the last year (17.1% males and 16.7% females). Multivariable analysis indicated several factors positively associated with SI: being bullied during the last 30 days (AOR= 2.15, 95%CI: 1.23-3.77), often feeling lonely in the last 12 months (AOR= 1.95, 95%CI: 1.10-3.44), worried and could not sleep at night in the last 12 months (AOR= 4.40, 95%CI: 2.64-7.34), tobacco use in the last 30 days (AOR= 3.76, 95%CI: 1.66-8.54), alcohol use in the last 30 days (AOR= 1.83, 95%CI: 1.26-2.65), no close friends (AOR= 2.03, 95%CI: 1.30-3.17), parents/guardians did not regularly check homework in the last 30 days (AOR= 1.57, 95%CI: 1.09-2.25), parents/guardians did not understand problems and worries of students in the last 30 days (AOR= 3.32, 95%CI: 2.04-5.42) and parents/guardians often displayed disrespect in the last 30 days (AOR= 1.63, 95%CI: 1.13-2.36). SI is widely recognized as a significant predictor of future suicide risk. Therefore, schools, parents, and policymakers need to urgently take measures to prevent deaths from occurring.