Doxycycline post-exposure prophylaxis (doxy-PEP) reduces chlamydia, gonorrhea, and syphilis infections among men who have sex with men (MSM) and transwomen (TW). Perspectives of health care providers (HCPs) regarding doxy-PEP can inform implementation efforts. From August 2022 to January 2023, HCPs were recruited from 13 cities with high sexually transmitted infection (STI) rates for semi-structured, in-depth interviews about their awareness of and attitudes towards doxy-PEP for STI prevention. HCPs were purposively sampled to include people with experience prescribing PrEP and provision of care to MSM. Interviews were conducted virtually via Zoom. Transcripts and debrief reports were analyzed using a directed content analysis approach to explore knowledge, attitudes, and beliefs about doxy-PEP. Among 30 HCPs, almost half (47%) were between 31-40 years of age, 53% identified as male, and 47% reported their sexual orientation as gay or queer. Half (53%) of participants practiced in the South, 43% had >100 MSM in their clinic panel, and 17% had previously prescribed doxy-PEP. We identified four overarching themes: 1) HCPs expressed positive attitudes towards doxy-PEP; 2) antimicrobial resistance concerns limit enthusiasm for some HCPs; 3) additional data about the long-term safety of doxy-PEP would improve their confidence; and 4) development of guidelines would facilitate the prescription of doxy-PEP, including eligibility, dosing instructions, and treatment management. HCPs were motivated to prescribe doxy-PEP with almost 20% already having prescribed it. Guidelines and data about long-term safety, especially antimicrobial resistance, would facilitate introduction of doxy-PEP into clinical practice.