In recent decays trends have been carried to use phytotherapy as an alternative to antibiotic therapy against bacterial fish diseases. Extracts or essential oils of many different medicinal herbs and plants have been tested for their in vitro antibacterial activities in vivo bioassay against fish pathogenic Streptococcus species, but more attentions have been paid to Streptococcus iniae and S. agalactiae isolated from diseased fish. The in vitro susceptibility of S. dysagalactiae and S. parauberis strains with fish origin have been also evaluated using various medicinal herbs, but there is no report on S. ubreis and S. phocae with fish origin. As different types of extractions, the extraction fractions and essential oils have been used for their antagonistic activity by different assays, it is therefore, difficult to compare the outcome results. This presentation addresses the efficacy and potency of medicinal herbs/plants as possible alternative to antibiotics for control and treatment of streptococcal infections in fish, and discuss the gaps required future works.