In order to collect basic data on the long-term load-bearing performance of adhesive post-installed anchors, experimental studies were conducted on the load-bearing performance of polyester resin post-installed anchors that had been used on a Metropolitan Expressway bridge for 39 years. All tensile tests failed due to bond failure between resin and concrete or a combination of bond failure and concrete cone failure. It was confirmed that the maximum loads of the tensile tests were lower than the newly installed anchor and the calculated value of bond strength (without considering of member coefficients). However, it is considered that the designed load-bearing performance is still ensured as the maximum load exceeds the allowable value used in the design.