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<p>Abstract</p> <p>Background</p> <p>Tularemia was reported in China over 50 years ago, however, many epidemical characteristics remain unclear. In the present study, the prevalence of <it>Francisella tularensis </it>in ticks was investigated during an epidemiological surveillance in China and then we measured their genetic diversity by conducting multiple-locus variable- number tandem repeat analysis (MLVA).</p> <p>Results</p> <p>1670 ticks from 2 endemic areas (Inner Mongolia Autonomous Region and Heilongjiang Province) and 2 non-endemic areas (Jilin and Fujian Provinces) were collected and tested for evidence of tularemia by nested PCR. The prevalence of <it>Francisella tularensis </it>in ticks averaged 1.98%. The positive rates were significantly different among tick species, with <it>Dermacentor silvarum </it>and <it>Ixodes persulatus </it>responsible for all positive numbers. All <it>F. tularensis </it>that were detected in ticks belonged to <it>F. tularensis </it>subsp. <it>holarctica </it>and MLVA disclosed genetic diversity. One subtype was identified in 17 of 33 positive tick samples in three different study areas. Another subtype belonging to <it>F. tularensis </it>subsp. <it>holarctica </it>genotype was described for the first time in the current study.</p> <p>Conclusion</p> <p>The study showed two tick species, <it>D. silvarum </it>and <it>I. persulatus </it>harboring the pathogen of tularemia in natural environment, indicating these two tick species might have a role in tularemia existence in China. MLVA results disclosed the genetic diversity <it>F. tularensis </it>and identified one genotype as the most prevalent among the investigated ticks in China.</p>