Chlamydia infections have been reported world wide with serious sequelae with sparse reports in developing countries. In Nigeria samples were collected from suspected cases and sometimes in healthy individuals in the six main geo-political zones of Nigeria. Sample collection was also done in the two main seasons of Nigeria. Samples included sputum, trhoat swab, endocervical swabs and urethral swabs. These samples were preserved according to the site of collection and analysed using specific and appropirate microbiological methods which included complement fixation test, immunochromatographic spot test, Romanowsky-Giemsa staining, culture. Characterization was done by chromosomal DNA isolation, plasmid DNA isolation, Polymerase Chain Reaction and Southern blot hybridization. There was a high prevalence of Chlamydia infection in all the geo-political zones from different infections. Most geo-political zones gave no variation except in some cases with Chlamydia pneumonia both geographically and seasonally. New suspected strains of Chlamydia were also identified from the pattern of cut by the enzyme endonucleases used to cut the DNAs.