Understanding knowledge of, attitudes toward, and willingness to use extreme risk protection order (ERPO) laws among law enforcement officers (LEOs) can inform efforts to improve implementation of this underused firearm violence prevention strategy. To characterize LEOs' knowledge of, attitudes toward, and willingness to use ERPOs across a range of scenarios. A cross-sectional online survey, fielded from April 5 to August 30, 2021, was conducted in all 19 states and the District of Columbia with an ERPO law in 2021. A nonprobability sample of active-duty LEOs was used. Being a LEO in a state with an ERPO law. Survey participants answered questions about their familiarity with and opinions on ERPO laws, as well as whether they would agree with using an ERPO in a variety of specific case scenarios. The analysis included an exploration of whether within-scenario differences, such as ERPO respondent race or gender, affected agreement by randomly assigning survey participants to 1 of 2 versions of each scenario. A total of 600 eligible individuals started the survey, and 283 survey participants were included in the analysis. The analytic sample consisted mostly of cisgender men (85.2%) and non-Hispanic White (71.4%) LEOs. Participants represented 14 states and the District of Columbia, with 53.7% living in California. Most participants (81.3%) were very or somewhat familiar with ERPO laws and 56.2% had received ERPO training. Opinions about ERPO laws were generally favorable but varied by self-identified political ideology. Across all scenarios, most participants supported using an ERPO; however, support was highest in cases involving intimate partner violence (71.4%-78.6%) and lowest in cases involving suicidality (54.2%-73.3%). Across all scenarios, LEOs with ERPO training or experience were substantially more likely to agree with using ERPOs than those without. None of the randomly assigned within-scenario differences were associated with differences in ERPO support. In this survey study of LEOs in states with ERPO laws, many officers had not received training on their use. Additionally, while conservative political ideology was associated with less favorable views of ERPOs, training and experience with ERPOs was associated with greater support for their use across a range of scenarios. These findings suggest that LEO training on ERPOs may promote their uptake and improve implementation.