Background: the medical laboratory service is a key component of the overall health system. rnThe service provides useful laboratory data to prevent, control, treat and follow up for patients.rnLocally derived reference interval (RI) is recommended to interpret laboratory data because therernare various physiological and environmental factors which affect it. There was no referencerninterval established for hematological parameters in Mekelle, Tigrai, Northern Ethiopia. rnObjective: Establishment of community based hematological reference intervals amongrnapparently healthy adults (18-60 years) in Mekelle, Tigrai, Northern Ethiopia from Decemberrn2018-May 2019: a cross sectional study. rnMethod: a cross-sectional study was employed in 344 apparently healthy adult (18-60)rnindividuals who live at least 5 years in Mekelle city, Tigrai, northern Ethiopia from Decemberrn2018-2019. About 4ml whole blood, stool and urine samples were collected. Hematologicalrnparameters were analyzed by Sysmex Kx-21 at Wukro hospital. Peripheral blood morphologyrnand malarial also were screened. The urine analysis, stool wet mount and Kato Katz werernexamined at collection sites and the formol-ether concentration was examined at the Tigrairnhealth research institute. Data were entered and analyzed using SPSS version 20. The 2.5rn andrn97.5rnthrn percentiles were calculated using non-parametric methods to determine 95% RI. rnResult: The established reference interval for hematological parameters were White blood cell:rn3-10x10rn9rn/L; lymphocyte percentage :19.6-57.6%; neutrophil percentage :24.91-70.3% for bothrnsexes (p>0.005); Red blood cell parameters were (p