A parasitic tapeworm, Echinococcus, causes hydatid disease. Disease is mostly seen in the abdominal and thoracic organs but can be seen in other tissues as well. Hydatid cysts of the extremities mostly present themselves in the subcutaneous region. Muscular hydatid cysts generally occur secondary to abdominal or thoracic hydatid disease. Primary muscular hydatidosis is a very rare disease and mostly seen in the gluteal and thigh muscles. Distal muscles are very rare localizations for primary muscular hydatidosis cases. In the treatment, surgical excision is the gold standard. Medical treatment is generally preferred after surgery. Here, we present an isolated infected primary muscular hydatid cyst in the deep posterior cruris muscles, which also surrounds the posterior neurovascular structures.