The importance of activins and follistatin in liver diseases has recently emerged. The aim of the present study was to measure the influence of chronic infection with viral hepatitis C (CHC) genotype 1 and 4 on serum levels of activin-A, activin-B and follistatin, and to determine their correlations with viral load, liver damage, interleukin-6 (IL-6) and tumour necrosis factor (TNF)-α. Sera samples collected from 20 male and 20 female treatment naïve CHC genotype 1 and 4 Saudi patients (ten males and ten females for each genotype), and 40 gender- and age-matched healthy participants were analysed for activin-A, activin-B and follistatin using enzyme-linked immunosorbent assay and their levels were correlated with IL-6, TNF-α, viral load and AST platelet ratio index (APRI). Serum activin-A, activin-B, IL-6 and TNF-α were significantly increased, while serum follistatin was significantly decreased, in both genders of CHC patients compared with control subjects, In both viral genotypes, activin-A was strongly and positively correlated with the viral load, APRI, IL-6 and TNF-α, and negatively with albumin (P < 0.01). Activin-B showed the same correlations of activin-A only in CHC genotype 1 patients, but it was weaker than activin-A. No correlation was detected with follistatin. Serum activins, particularly activin-A, and follistatin are significantly altered by CHC genotype 1 and 4. This dysregulation of activins/follistatin axis may be associated with viral replication, host immune response and liver injury. Further studies are needed to illustrate the definite role(s) and clinical value of activins and follistatin in CHC.