Feces (n = 226; 2004–2015) from healthy captive and wild blue iguanas (Cyclura lewisi) from Grand Cayman, Cayman Islands, were examined for endoparasites. Parasites identified included Nyctotherus sp. and Entamoeba sp. cysts and trophozoites, trichomonad trophozoites, and oxyurid and trichostrongylid eggs. Endoparasites from postmortem examinations (n = 13) included adult and larval nematodes: Ozolaimus megatyphlon, Ozolaimus monhystera, Alaeuris travassosi, Atractis mega, and an unidentified species of Oswaldocruzia. Entamoeba spp. were more likely in captive juveniles of both sexes than captive or wild adults of either sex; Entamoeba spp. were more likely in captive adult females than captive adult males; trichomonad trophozoites were more likely in adult captive and wild iguanas of both sexes than in captive juveniles of either sex; and Nyctotherus spp. were more likely in juvenile captive males than captive adult males or females and more likely in adult wild males than captive juvenile males. Trichostrongylid eggs were more likely in adult wild females than adult captive females and more likely in captive and wild adults of both sexes than in captive juveniles of both sexes. Oxyurid eggs were more likely in adult captive and wild iguanas of both sexes than captive juveniles of either sex. Blue iguanas have a variety of endoparasites regardless of age, sex, or captive vs wild status, with no type found exclusively in either captive or wild populations. Ectoparasites from wild adults included adult ticks (Amblyomma torrei) and a single adult mite (Hirstiella trombidiformis). All are new host records for this species and Grand Cayman. Knowledge of parasite status of captive and wild populations is important to evaluate the relative risk of introduction of captive animals into wild populations.