The infectious diseases have a devastating effect in the culture of marine shrimp, being an economic obstacle and threat to the activity.  The diagnosis of the state of health of cultivated shrimps allows that actions are taken to control, to minimize or to exclude the negative effect on the shrimp production, reducing the financial, social and ecological damages. The infections of the shrimp can be caused by bacteria, virus, fungi, protozoans and metazoans. Among the virus existing in Brazil, the Infectious Hipodermal and Hematopoietic Necrosis Virus (IHHNV) cause great concern to the development of the carciniculture.  The objective of this work was to compare the diagnosis of the IHHNV by the histopathologic procedures and polimerase chain reaction (PCR).  Thirty samples of shrimp of three ponds, being ten of each pond, were collected of one farm located in the city of Canguaretama/RN, that were analysed by PCR and histopathologic method.  For accomplishment of the PCR, DNA were collected  from hemolymph and pleopods. The other tissues were put in Davidson’s fixative and submitted to histopathologic processing. For the amplification of the DNA of IHHNV, a specific pair of primers was used and the product was analysed by eletrophoresis in poliacrylamide and stained by the silver.  For the histopathologic procedures, tissues were sectionated in thin layers, stained by hematoxylin/eosin and observed in optical microscope. Samples considered positive presented Cowdry Inclusion Bodies (CAI), characteristic of the infection by the IHHNV.  Two ponds (A and B) presented positive samples for IHHNV.  The positivity by PCR and histopathologic method, was respectively 20% (6/30) and 10% (3/30).  Although the high specificity and sensibility of the PCR, this technique does not quantify the infection while the histopathologic method makes it. However, the last one is susceptible to errors, mainly when exist histopathological similarities among differents viral infections. Moreover, this technique does not diagnoses the infection when the virus is found in low levels.  In the diagnosis of IHHNV, the PCR and histopathological procedures must be executed, being the first used for identification and the second for  quantification.