The attachment of epiphytes on culture equipment and seaweed thalli has proven to be one of the factors preventing Eucheuma denticulatum growth. This research aimed to clarify epiphyte preference for E. denticulatum thallus and culture equipment by using vertical nets. Vertical net is a cultivation technology that protects seaweeds from herbivorous pests (fish and turtles). This research was conducted at Tanjung Tiram Coast, one of seaweed cultivation areas in Southeast Sulawesi Province, Indonesia. This research used vertical nets and E. denticulatum thalli. The study took place at 3 stations, each using 3 tools and 3 replications. The results showed that there were 7 species of epiphyte attaching to the vertical net equipment and 6 species attaching to the thalli of E. denticulatum. The densities of epiphytes attaching to the vertical net equipment and E. denticulatum thalli were 110 ind./cm2 and 250 ind./cm2 on average, respectively. Statistical analysis showed no significant difference in density between the epiphytes attached to the vertical net equipment and those attached to the E. denticulatum thalli. They also showed that the epiphyte density insignificantly influenced the overall seaweed weight. Correlation analysis showed a significant correlation between the abundance of epiphytes attached to the vertical nets and brightness.