Implementation of a standardized language in Nursing Care Plans (SNCP) allows for increased efficiency in nursing data management. However, the potential relationship with patientś health outcomes remains uncertain. The aim of this study was to evaluate the effectiveness of SNCP implementation, based on North American Nursing Diagnosis Association (NANDA) and Nursing Interventions Classification (NIC), in the improvement of metabolic, weight, and blood pressure control of Type 2 Diabetes Mellitus (T2DM) patients. A two-year prospective follow-up study, in routine clinical practice conditions. 31 primary health care centers (Spain) participated with 24,124 T2DM outpatients. Data was collected from Computerized Clinical Records; SNCP were identified using NANDA and NIC taxonomies. Descriptive and ANCOVA analyses were conducted. 18,320 patients were identified in the Usual Nursing Care (UNC) group and 5,168 in the SNCP group. At the two-year follow-up, the SNCP group improved all parameters except LDL cholesterol and diastolic blood pressure. We analyzed data adjustming by the baseline value for these variables and variables with statistically significant differences between groups at baseline visit. Results indicated a lowering of all parameters except HbA1c, but a statistically significant reduction was only observed with diastolic blood pressure results. However, the adjusted reduction of diastolic blood pressure is of little clinical relevance. Greater differences of control values for diastolic blood pressure, HbA1c, LDL-cholesterol and Body Mass Index were found in the SNCP group, but only reached statistical significance for HbA1c. A greater proportion of patients with baseline HbA1c ≥7 decreased to <7% at the two-year follow-up in the SNCP group than in the UNC group (16.9% vs. 15%; respectively; p = 0.01). Utilization of SNCP was helpful in achieving glycemic control targets in poorly controlled patients with T2DM (HbA1c ≥7%). Diastolic blood pressure results were slightly improved in the SNCP group compared to the UNC group. ClinicalTrials.gov NCT01482481.