Bromelain is a collective name for proteolytic enzymes or proteases (natural proteolytic enzymatic complex) found in tissues including stems, fruit and leaves of the pineapple (Ananas comosus var. comosus) and of other plant species of the family Bromeliaceae (KUMAR, 2011). Is a bioactive agent possessing remarkable therapeutic properties such as reversible inhibition of platelet aggregation, relief from bronchitis, sinusitis and enhanced absorption of drugs, particularly of antibiotics (BHUI et al., 2009). Although Brazil is a major producer of pineapple, occupying the first position in 2010 worldwide with a production of 1.5 million tons of fruit, the salt stress, deleterious alterations observed in plants grown in saline conditions, which occur due to intoxication by ions and decline of supply of water and nutrients to the plant (LI et al., 2010), is main factor limiting growth and productivity of plants since it causes metabolic responses in plants, affecting and compromising all important processes such as photosynthesis, changes in levels and protein synthesis and activity enzymes, as well as in the synthesis of lipid metabolism and energy (PIZA et al., 2003). Thus, the objective of this research was to evaluate the influence of salt stress on the activity of bromelain in pineapple plants (Ananas comosus L. Merril) cv. Perola cultured in vitro.