Risk factors for Salmonellosis in pigs were investigated in a cross-sectional study on 62 Belgian farrow-to-finish herds belonging to one slaughterhouse co-operation. Herd data were collected using a questionnaire. The outcome variable, the percentage of positive animals per slaughterhouse delivery, was determined by qualitative Salmonella isolation from the mesenterial lymph nodes. Variables significantly related to the Salmonella prevalence in the univariate analyses were subsequently analysed in a multivariate model. Furthermore, the clustering of Salmonella infection within the pen was studied. The median percentage of positive samples per delivery was 64.5%. In the multivariate model, only type of floor significantly influenced the prevalence independently (p<0.05) with a fully slatted floor leading to the lowest Salmonella prevalence. Clustering between pigs from the same pen could not be demonstrated. The risk factors investigated here could only explain a small amount of the variability between herds.