Mastitis is an economically important production disease in Bangladesh. A cross-sectional study was conducted to determine the association of udder lesions with Subclinical Mastitis (SCM) in dairy cows of Chattogram Metropolitan Area (CMA) and Patiya Upazila of Chattogram district during the period from December 2017 to May 2018. For this, 264 milk samples and 155 swab samples were collected from 50 different dairy farms available in CMA and Patiya Upazila. A pretested questionnaire was implemented during sample collection for identifying the associated risk factors of udder lesions and SCM, and to identify the association of udder lesions with SCM. Clinical inspection, palpation and observation were the main tools for determining the udder lesions whereas California Mastitis Tests (CMT) were used for the diagnosis of SCM. Milk samples from CMT positive cows and swab samples from cows' udder surface with lesions were collected for laboratory analysis. Laboratory analysis including bacterial culture and biochemical tests were done to identify the causal agents of SCM and udder lesions. The overall prevalence of SCM and udder lesions were 56.8% and 32.1%, respectively. Most of the farms under study were small scale (94%) except a few were medium-scale (6%). Very few farms used quarantine and isolation shed (6%) for the disease affected cows. Among the risk factors identified; type of farm, floor type, quarantine facility, isolation shed used, adequate drainage facility were statistically significant (P ≤ 0.05) to causing both SCM and udder lesions. Predominant causal agents isolated were Staphylococcus sp 186 (70.4%), Streptococcus sp 146 (55.3%), Bacillus sp 62 (23.5%) and E. coli 20 (7.6%) from collected CMT positive milk samples. Bacterial cultures of swab samples of udder lesions revealed Staphylococcus sp 120 (77.4%), Streptococcus sp 112 (72.2%), E. coli 110 (71.0%), and Bacillus sp 47 (30.3%). Moreover, udder lesions were associated with the occurrence of SCM in dairy cows. Therefore, udder damages should be managed carefully to minimise SCM prevalence in dairy cows.