The prevalence of chronic Lyme disease (CLD) remains relatively unknown in Connecticut because there is not an agreement on what CLD is and how it should be diagnosed in addition to which pathological agent causes CLD. The aim of this quantitative study was to assess whether there were significant differences between two groups of primary care physicians (PCP) working in Connecticut from two different points in time regarding their knowledge in the diagnosis, treatment, and management of CLD. A knowledge, attitude, and practice model was used as the underlying theoretical framework for this study. A random cross-sectional survey was mailed out to the 1,726 PCPs found in the list of certified medical doctors in Connecticut of 2015. One hundred and forty-five PCPs responses (11.9% response rate) were received and compared to responses from previous data (a 2010 study) of 285 PCPs (39.1% response rate) from the list of certified medical doctors in 2006. The PCP estimated mean number of patients diagnosed and treated for CLD was not significantly different between 2006 and 2015. However, a significantly higher number of PCPs in 2015 reported knowing Lyme disease (LD) symptoms but not feeling comfortable diagnosing LD (χ� = 536.83, p < 0.001), and significantly more PCPs in 2015 reported knowing LD symptoms and feeling comfortable diagnosing CLD (χ� = 265.41, p < 0.001). This study can promote social change by encouraging Connecticut PCPs to recognize CLD as a diagnosis to enable the development of registries and case-control assessments. The findings of this study may also inspire future studies.