A travel assistance method comprising: detecting, by a sensor of a host vehicle (C1), surroundings of the host vehicle (C1); generating a first traveling path (P1) based on the surroundings; and executing travel assistance control of the host vehicle (C1) based on the first traveling path (P1), wherein the method comprises: generating a second traveling path (P2); determining whether the first traveling path (P1) and the second traveling path (P2) have likeness; and switching a traveling path that the host vehicle (C1) is caused to follow by the travel assistance control; characterized in that : the second traveling path (P2) is generated based on high-definition map information around a circumference of the host vehicle (C1); switching the traveling path that the host vehicle (C1) is caused to follow by the travel assistance control is performed from the first traveling path (P1) to the second traveling path (P2) when the first traveling path (P1) and the second traveling path (P2) are determined to have likeness, and by generating the first traveling path (P1) again when the first traveling path (P1) and the second traveling path (P2) are determined to have no likeness. detecting, by a sensor of a host vehicle (C1), surroundings of the host vehicle (C1); generating a first traveling path (P1) based on the surroundings; and executing travel assistance control of the host vehicle (C1) based on the first traveling path (P1), wherein the method comprises: generating a second traveling path (P2); determining whether the first traveling path (P1) and the second traveling path (P2) have likeness; and switching a traveling path that the host vehicle (C1) is caused to follow by the travel assistance control; characterized in that : the second traveling path (P2) is generated based on high-definition map information around a circumference of the host vehicle (C1); switching the traveling path that the host vehicle (C1) is caused to follow by the travel assistance control is performed from the first traveling path (P1) to the second traveling path (P2) when the first traveling path (P1) and the second traveling path (P2) are determined to have likeness, and by generating the first traveling path (P1) again when the first traveling path (P1) and the second traveling path (P2) are determined to have no likeness. generating a second traveling path (P2); determining whether the first traveling path (P1) and the second traveling path (P2) have likeness; and switching a traveling path that the host vehicle (C1) is caused to follow by the travel assistance control; characterized in that : the second traveling path (P2) is generated based on high-definition map information around a circumference of the host vehicle (C1); switching the traveling path that the host vehicle (C1) is caused to follow by the travel assistance control is performed from the first traveling path (P1) to the second traveling path (P2) when the first traveling path (P1) and the second traveling path (P2) are determined to have likeness, and by generating the first traveling path (P1) again when the first traveling path (P1) and the second traveling path (P2) are determined to have no likeness. the second traveling path (P2) is generated based on high-definition map information around a circumference of the host vehicle (C1); switching the traveling path that the host vehicle (C1) is caused to follow by the travel assistance control is performed from the first traveling path (P1) to the second traveling path (P2) when the first traveling path (P1) and the second traveling path (P2) are determined to have likeness, and by generating the first traveling path (P1) again when the first traveling path (P1) and the second traveling path (P2) are determined to have no likeness. <EOS>