Tuberculosis (TB) remains an important public health concern, and timely laboratory diagnosis is essential for effective case detection and disease control. This cross-sectional study assessed TB diagnostic laboratory capacity in selected laboratories within Meru Municipality, Meru County, Kenya. Twenty-six laboratory technicians/technologists from nine laboratories were selected using stratified random sampling. Data were collected using a semi-structured questionnaire and an observational checklist covering laboratory infrastructure, diagnostic tests, equipment, reagents, record management, laboratory information systems and internet access. Chi-square analysis was used to assess differences between selected study variables. All assessed laboratories offered Ziehl-Neelsen staining (100%, n = 9), and all respondents reported availability of microscopes, electricity, running water and Ziehl-Neelsen reagents. Most respondents reported TB record management (88.5%, n = 23), laboratory information system availability (84.6%, n = 22), internet access (76.9%, n = 20) and centrifuges (84.6%, n = 22). However, no laboratory offered PCR restriction enzyme assay or sputum TB culture and sensitivity testing. Fluorescence microscopy and the Gene Xpert assay were each available in one laboratory (11.1%, n = 1). Public laboratories showed comparatively stronger TB diagnostic capacity than private commercial laboratories. The findings indicate basic microscopy-based capacity but notable gaps in molecular, culture and drug-susceptibility testing capacity.