Hemoplasmas are epi-erythrocytic parasites which have been reported in several mammalian species, including dogs. Infections may lead to hemolytic anemia, but investigations in the dog are scarce and had been hampered by the lack of adequate diagnostic methods. The aim of this study was to detect hemoplasma infection in dogs from Tocantins State, Brazil, and associate hematological disorders to the disease. Blood samples from 96 dogs were submitted to real-time PCR (qPCR) based on the gene encoding 16S rRNA for the detection of Mycoplasma spp. Next, a standard PCR using primer pair specific for Mycoplasma haemocanis, 'Candidatus Mycoplasma haematoparvum'/'Candidatus Mycoplasma haemominutum' and 'Candidatus Mycoplasma turicensis' was performed. Among all dogs, 26% were positive by qPCR. The infection frequency of M. haemocanis was 13.54%, while 'Candidatus Mycoplasma haematoparvum'/'Candidatus Mycoplasma haemominutum' and 'Candidatus Mycoplasma turicensis' were not detected. Anemia was detected in 70% of the animals positive for M. haemocanis, being the major hematological disorder associated with infection. The results demonstrate the occurrence of M. haemocanis in the canine population of Tocantins State and denote their potential to cause anemia in dogs. Therefore, future studies are necessary in order to characterize this agent and the issues involved in its transmission and pathogenic potential among Brazilian dogs.