A simulation system comprising: a simulation unit configured to virtually execute an operation program including a path representing a trajectory of a robot, on a virtual space in which the robot and another object are arranged; an interference checking unit configured to check whether there is an interference between the robot and the other object based on an execution result of the operation program; and an adjustment unit configured to adjust a parameter related to at least one teaching point corresponding to the path in response to detecting the interference, in order to eliminate the interference, wherein the operation program includes a work path and an air-cut path, the work path being set based on a user input and indicating a first trajectory of the robot in a task, the air-cut path being automatically set and indicating a second trajectory of the robot connecting tasks, and the simulation unit is configured to: virtually execute a unitary operation program which is a part of the operation program that relates to the air-cut path; and in response to no interference occurring in the air-cut path, further virtually execute a continuous operation program which is a part of the operation program that relates to a sequence of the work path and the air-cut path, and the adjustment unit is configured to adjust the parameter related to the at least one teaching point corresponding to the air-cut path without changing the work path, in response to detecting the interference in the air-cut path. a simulation unit configured to virtually execute an operation program including a path representing a trajectory of a robot, on a virtual space in which the robot and another object are arranged; an interference checking unit configured to check whether there is an interference between the robot and the other object based on an execution result of the operation program; and an adjustment unit configured to adjust a parameter related to at least one teaching point corresponding to the path in response to detecting the interference, in order to eliminate the interference, wherein the operation program includes a work path and an air-cut path, the work path being set based on a user input and indicating a first trajectory of the robot in a task, the air-cut path being automatically set and indicating a second trajectory of the robot connecting tasks, and the simulation unit is configured to: virtually execute a unitary operation program which is a part of the operation program that relates to the air-cut path; and in response to no interference occurring in the air-cut path, further virtually execute a continuous operation program which is a part of the operation program that relates to a sequence of the work path and the air-cut path, and virtually execute a unitary operation program which is a part of the operation program that relates to the air-cut path; and in response to no interference occurring in the air-cut path, further virtually execute a continuous operation program which is a part of the operation program that relates to a sequence of the work path and the air-cut path, and the adjustment unit is configured to adjust the parameter related to the at least one teaching point corresponding to the air-cut path without changing the work path, in response to detecting the interference in the air-cut path.