IMPORTANCE The management of noncommunicable diseases in humanitarian crises has been slow to progress from episodic care. Understanding disease burden and access to care among crisisaffected populations can inform more comprehensive management. OBJECTIVE To estimate the prevalence of hypertension and diabetes with biological measures and to evaluate access to care among Syrian refugees in northern Jordan. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study was undertaken from March 25 to April 26, 2019, in the districts of Ramtha and Mafraq, Jordan. Seventy clusters of 15 households were randomly sampled, and chain referral was used to sample Syrian households, representative of 59 617 Syrian refugees. Adults were screened and interviewed about their access to care. Data analysis was performed from May to September 2019. EXPOSURES Primary care delivered through a humanitarian organization since 2012. MAIN OUTCOMES AND MEASURES The main outcomes were self-reported prevalence of hypertension and diabetes among adults aged 18 years or older and biologically based prevalence among adults aged 30 years or older. The secondary outcome was access to care during the past month among adults aged 18 years or older with a diagnosis of hypertension or diabetes. RESULTS In 1022 randomly sampled households, 2798 adults aged 18 years or older, including 275 with self-reported diagnoses (mean [SD] age, 56.5 [13.2] years; 174 women [63.3%]), and 915 adults aged 30 years or older (608 women [66.5%]; mean [SD] age, 46.0 [12.8] years) were screened for diabetes and hypertension. Among adults aged 18 years or older, the self-reported prevalence was 17.2% (95% CI, 15.9%-18.6%) for hypertension, 9.8% (95% CI, 8.6%-11.1%) for diabetes, and 7.3% (95% CI, 6.3%-8.5%) for both conditions. Among adults aged 30 years or older, the biologically based prevalence was 39.5% (95% CI, 36.4%-42.6%) for hypertension, 19.3% (95% CI, 16.7%-22.1%) for diabetes, and 13.5% (95% CI, 11.4%-15.9%) for both conditions. Adjusted for age and sex, prevalence for all conditions increased with age, and women had a higher prevalence of diabetes than men (adjusted prevalence ratio, 1.3%; 95% CI, 1.0%-1.7%), although the difference was not significant. Complications (57.4%; 95% CI, 51.5%-63.1%) and obese or overweight status (82.8%; 95% CI, 79.7%-85.5%) were highly prevalent. Among adults aged 30 years or older with known diagnoses, 94.1% (95% CI, 90.9%-96.2%) currently took medication. Among adults aged 18 years or older with known diagnoses, 26.8% (95% CI, 21.3%-33.1%) missed a medication dose in the past week, and 49.1% (95% CI, 43.3%-54.9%) sought care in the last month. CONCLUSIONS AND RELEVANCE During this protracted crisis, obtaining care for noncommunicable diseases was feasible, as demonstrated by biologically based prevalence that was (continued)