Community health worker (CHW) intervention is a promising approach to address type 2 diabetes among Latinos. However, evidence from randomized clinical studies is limited. To compare a CHW intervention with enhanced usual care. This 52-week, single-blind, randomized clinical trial included 300 Latino adults aged 18 to 65 years who were treated in 2 public hospital outpatient clinics in Miami-Dade County, Florida, from July 1, 2010, through October 31, 2013. Eligible participants had a hemoglobin A1c (HbA1c) level of 8.0 or greater. Follow-up was completed January 31, 2015, and data were analyzed from March 10, 2015, to June 6, 2016. A 1-year CHW intervention consisted of home visits, telephone calls, and group-level activities. Primary outcomes included systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDLC) levels, and HbA1c levels. Secondary outcomes included body mass index, medication regimen intensification, and self-reported measures of diet, physical activity, and medication regimen adherence. Of the 300 participants randomized (135 men [45%] and 165 women [55%]; mean [SD] age, 55.2 [7.0] years), we obtained follow-up data on 215 (71.7%). Participants in the CHW group received a median of 4 home visits and 20 telephone calls. After adjusting for baseline values and covariates, participants in the CHW group had an HbA1c level that was 0.51% lower (95% CI, -0.94% to -0.08%) than that of participants in the enhanced usual care group. The reduction in SBP of 4.62 mm Hg (95% CI, -9.01 to -0.24 mm Hg) did not meet the preplanned target of 8 mm Hg and was not statistically significant in unadjusted models. No significant differences in LDLC levels (mean difference, -8.2 mg/dL; 95% CI, -18.8 to 2.3 mg/dL) or any of the preplanned secondary outcomes were observed. Post hoc analyses suggest that the intervention may be more beneficial among those with worse control of their type 2 diabetes at baseline. Among Latinos with poorly controlled type 2 diabetes, a 12-month CHW intervention lowered HbA1c levels by 0.51%. The intervention did not lead to improvements in LDLC levels, and the findings with respect to SBP were variable and half of what was targeted. Future studies should examine whether CHW interventions affect other measures, such as access to health care or social determinants of health. clinicaltrials.gov Identifier: NCT01152957.