Weed control around electric and mesh animal fences surrounding fields is effective for preventing animal damage. Robotic mowers are effective for labor saving in weed control in the near space of animal fences, mesh fence and electric fence. Because robotic mowers attack the posts for mesh fences and touch the electric wires in electric fences when weeding, some troubles in fence management are expected. Practical experiments were conducted in weeding work with robotic mower around mesh and electric fences. Results did not indicate that the robotic mower exacerbated loosening of the mesh fence posts. In some cases, loosening of the posts progressed either with or without robotic mower usage. To prevent fence collapse, checking and refixing the mesh fence posts once a year is considered effective, irrespective of whether robots are used. Practical experiments conducted around electric fences revealed that the robotic mower can control weeds under the electric wire. Furthermore, a simple tensioner consisting of a spring and pulley to prevent loosening of the electric wire was produced and tested. Findings demonstrated that the tensioner can mitigate and prevent loosening of the wire when the mower height is about 100 mm higher than the electric wire height. Because of the robotic mower structure, weeds around the posts are left uncut. To keep the weed height around the posts lower than the lower electric wire （200 mm height）, some measures must be used at least once a month.