Open AccessThe effects of managerial systems on the occurrence of gastrointestinal helminths in Free-Range Chickens (FRCs) from northern Paraná, Brazil were investigated. The most predominant (23.3%; 61/262) cestode observed was Raillietina cesticillus; Heterakis gallinarum (71.4%; 187/262) and Ascaridia galli (45%; 118/262) were the predominant nematodes; Postharmostomum commutatum was the only trematode observed in 2.7% (7/262) of FRCs. The most elevated parasitic burdens were associated with Heterakis gallinarum, Ascaridia galli, and Raillietina cesticillus. Significant (p ? 0.05) associations were observed when the effects of the types of bedding, soil type, and fence restriction of FRCs were considered relative to the possibility of helminthiasis. The type of bedding, the length of the sanitary break, and the presence of shading significantly (p ? 0.05) influenced the possibility of FRCs being infected by H. gallinarum. Most parameters evaluated were significantly associated with infection of FRCs by A. galli. These findings suggest that FRCs from northern Paraná are infected by a wide-range of gastrointestinal helminths, but more frequently by R. cesticillus, H. gallinarum, and A. galli. Moreover, the type of floor bedding, the soil type, and the usage of fences in the management of FRCs is directly related to gastrointestinal helminthiasis.