Background: No previous studies have examined the association between attitudes and beliefs of chiropractors and their adherence to low back pain (LBP) guidelines. The aim of this study is: (1) to assess the attitudes and beliefs towards the management of LBP of Dutch and Belgian chiropractors; and (2) to investigate the association of these attitudes and beliefs on the use of diagnostic imaging and on the adherence to diagnostic guidelines and guidelines in the management of patients with LBP. Methods: Study design: Cross-sectional study using a web-based questionnaire in chiropractic private practices in the Netherlands and Belgium. The survey included sociodemographic characteristics, use of diagnostic imaging, the Pain Attitude and Beliefs Scale-Physiotherapists (PABS.PT) and 6 vignettes (3 acute and 3 chronic LBP patients). We used Latent Profile Analysis (LPA) to categorise the chiropractors into clusters depending on their PABS.PT outcome, whereby the classes differed primarily on the biomedical score. We used linear, logistic, and mixed models to examine the associations between these clusters, and adherence to the recommendations of guidelines on: (1) diagnostic imaging use, and (2) management of LBP (i.e. advice on activity, treatment, return-to-work, and bedrest). Results: The response rate of the Dutch and Belgian chiropractors was 61% (n = 149/245) and 57% (n = 54/95), respectively. The majority of chiropractors scored midrange of the biomedical scale of the PABS.PT. Three clusters were identified using LPA: (1) high biomedical class (n = 18), (2) mid biomedical class (n = 117) and (3) low biomedical class (n = 23). Results from the vignettes suggest that chiropractors in the high biomedical class better adhere to diagnostic imaging guidelines and to LBP guidelines when it concerns advice on return-to-work and activity compared to the other two classes. However, no differences were identified between the classes for treatment of LBP. All chiropractors adhered to the guidelines’ recommendation on ...