Deficiencies in advance care planning and symptom management are associated with avoidable acute care use among patients with cancer. Community health worker (CHW)–led approaches may be an approach to reduce acute care use but remain untested in community settings. The objective of this study was to determine whether a CHW-led advance care planning and symptom screening intervention can reduce acute care use more than usual care in a community setting. This randomized clinical trial was conducted among patients with newly diagnosed advanced-stage or recurrent solid and hematologic cancers from August 8, 2017, through November 30, 2021. Data analysis was performed November 30, 2021, through January 1, 2022, by intention to treat. Participants were randomized 1:1 to usual care (control group) or usual care with the 6-month CHW-led intervention (intervention group). The primary outcome was acute care use. Secondary outcomes included advance care planning documentation, supportive care use, patient-reported outcomes, survival, and end-of-life care use. Among 128 participants, median (range) age was 67 (19-89) years; 61 (47.7%) were female; and 2 (1.6%) were American Indian or Alaska Native, 11 (8.6%) were Asian, 5 (3.9%) were Black, 23 (18.0%) were Hispanic or Latino, 2 (1.6%) were of mixed race, 2 (1.6%) were Native Hawaiian or other Pacific Islander, 86 (67.2%) were White, and 20 (15.6%) did not report race. Intervention participants had 62% lower risk of acute care use than the control (hazard ratio, 0.38; 95% CI, 0.19-0.76) within 6 months. At 12 months, intervention participants had 17% lower odds of acute care use (odds ratio [OR], 0.83; 95% CI, 0.69-0.98), 8 times the odds of advance care planning documentation (OR, 7.18; 95% CI, 2.85-18.13), 4 times the odds of palliative care (OR, 4.46; 95% CI, 1.88-10.55), nearly double the odds of hospice (OR, 1.83; 95% CI, 1.16-2.88), and nearly double the odds of improved mental and emotional health from enrollment to 6 and 12 months postenrollment (OR, 1.82; 95% CI, 1.03-3.28; and OR, 2.20; 95% CI, 1.04-4.65, respectively) than the control. There were no differences in the death (control, 26 [40.6%] vs intervention, 32 [50.0%]). Fewer intervention participants had acute care use (0 vs 6 [23.1%]) in the month before death than the control. In this randomized clinical trial, integration of a CHW-led intervention into cancer care reduced acute care use and is one approach to improve cancer care delivery for patients with advanced stages of disease in community settings.