PURPOSE: To provide a linear actuator whose size can be reduced with efficiency increased without increasing the cost of components and whose vibration noise can also be eliminated.

CONSTITUTION: This actuator is provided with a coil moving frame 2 having a driving coil 7, a first body tube member 9 having guide sections 3, 4 for the coil moving frame 2, a U-shaped yoke 10 on which a permanent magnet 8 is installed and which has the driving coil 7 being passed through its side piece 16, a second body tube member 17, sub yokes 11 which are installed at both ends of the U-shaped yoke 10. The first body tube member 9 and the U-shaped yoke 10 are so positioned as to fit in with each other and the second body tube member 17 and the sub yokes 11 are positioned with an elastic member 23 being placed between them.