Aim of this study was to evaluate the occurrence of Mycoplasma (M.) haemofelis, Candidatus Mycoplasma (C. M.) turicensis, C M. haemominutum, Bartonella spp. (B. henselae, B. clarridgeiae and B. quintana) and Anaplasma (A.) phagocytophilum in cats in Northeast Germany in relation to their living conditions (indoor/outdoor/ stray cat), and tick/flea exposure. 265 cats were included in the study (150 indoor, 99 outdoor access, 16 stray cats). A questionnaire provided the following data: derivation, housing environment, and previous flea/tick exposure. Serum antibody titers against A. phagocytophilum, B. henselae, and B. quintana were determined by an immunofluorescence test (IFT). PCR tests (EDTA blood) were used to test for A. phagocytophilum, M. haemofelis, C. M. turicensis, C. M. haemominutum, B. henselae and B. clarridgeiae. In 19 of 265 cats (7.2%) DNA of one or more Mycoplasma spp. was detected: C M. haemominutum (5.3%), M. haemofelis (1.5%) and C M. turicensis (1.1%); three of the cats were tested positive for the feline immunodeficiency virus. All cats were B. henselae and B. clarridgeiae PCR-negative in peripheral blood. However, 91 of 245 cats (37.1%) had antibody titers > 1:200 for B. henselae (Houston I, Marseille type) and 46 (18.8%) for B. quintana. Antibody titers > 1:64 against A. phagocytophilum were detected in 24 cats (9.1%); one cat (0.4%) was PCR-positive. Since infections with haemotropic Mycoplasma spp. and also with arthropodborne organisms (Bartonella spp., A. phagocytophilum) occur in cats from the area Berlin/Brandenburg (Germany) an appropriate arthropod-control is recommended. Further studies are needed to evaluate the relevance of these infectious agents for the individual cat.