Since TBX agar has been successfully used for E. coli detection and enumeration in food microbiology by colony counting technique, with or without using membrane filters, the idea was to examine whether it could be used to detect and enumerate E. coli in bathing seawater samples. This paper presents the results of the membrane filtration method for counting E. coli in seawater samples using TBX agar. Different media were used for test method: TBX agar, single-layered MMGA and TBX agar, and double-layered MMGA/TBX agar. To determine the basic performance characteristics of TBX agar, different volumes of natural samples were filtered and incubated on the selected medium under different incubation conditions. The results suggested that pre-incubation in mild conditions (36±2°C) on non-selective medium (MMGA) significantly increases the recovery of bacterial cells, resulting in higher number of E. coli. Incubation at 44±0.5°C on double-layered MMGA/TBX with 6-hour pre-incubation at 36± 2°C and alternate incubation, 4-hour pre-incubation on MMGA at 36±2°C followed by 20-hour incubation on TBX at 44±0.5°C, resulted in acceptable relative recovery of E. coli. The achieved performance characteristics are acceptable and both procedures could be used for E. coli detection and enumeration in bathing seawater samples.