A lens position adjustment device comprising: a lens holder holding a lens (104, 222); a first shape memory alloy wire (210, 610) configured to move the lens holder in a first direction along an optical axis of the lens (104, 222); and a second SMA wire (212, 612) configured to move the lens holder in a second direction along the optical axis, the second direction being opposite to the first direction, in which: the lens holder is moved in the first or second direction along the optical axis through energizing the first SMA wire (210, 610) and the second SMA wire (212, 612) and controlling a force that moves the lens holder; wherein a housing of the lens position adjustment device includes a guiding section (214, 216), the lens holder includes an engaging section configured to be brought into engagement with the guiding section (214, 216) such that the lens holder is allowed to be moved along the optical axis, the lens holder is guided by the guiding section (214, 216) and moved along the optical axis, and the first SMA wire (210, 610) and the second SMA wire (212, 612) bias the lens holder at the position where the lens holder is held such that the lens holder is biased inward from a side of the lens holder, wherein an orientation of an inwardly biasing force is deviated by a predetermined angle from a direction from the side to the center of the lens (104, 222), and the engaging section and the guiding section (214, 216) are brought into contact with each other by the inwardly biasing force. a lens holder holding a lens (104, 222); a first shape memory alloy wire (210, 610) configured to move the lens holder in a first direction along an optical axis of the lens (104, 222); and a second SMA wire (212, 612) configured to move the lens holder in a second direction along the optical axis, the second direction being opposite to the first direction, in which: the lens holder is moved in the first or second direction along the optical axis through energizing the first SMA wire (210, 610) and the second SMA wire (212, 612) and controlling a force that moves the lens holder; wherein a housing of the lens position adjustment device includes a guiding section (214, 216), the lens holder includes an engaging section configured to be brought into engagement with the guiding section (214, 216) such that the lens holder is allowed to be moved along the optical axis, the lens holder is guided by the guiding section (214, 216) and moved along the optical axis, and the first SMA wire (210, 610) and the second SMA wire (212, 612) bias the lens holder at the position where the lens holder is held such that the lens holder is biased inward from a side of the lens holder, wherein an orientation of an inwardly biasing force is deviated by a predetermined angle from a direction from the side to the center of the lens (104, 222), and the engaging section and the guiding section (214, 216) are brought into contact with each other by the inwardly biasing force. the lens holder is moved in the first or second direction along the optical axis through energizing the first SMA wire (210, 610) and the second SMA wire (212, 612) and controlling a force that moves the lens holder; wherein a housing of the lens position adjustment device includes a guiding section (214, 216), the lens holder includes an engaging section configured to be brought into engagement with the guiding section (214, 216) such that the lens holder is allowed to be moved along the optical axis, the lens holder is guided by the guiding section (214, 216) and moved along the optical axis, and the first SMA wire (210, 610) and the second SMA wire (212, 612) bias the lens holder at the position where the lens holder is held such that the lens holder is biased inward from a side of the lens holder, wherein an orientation of an inwardly biasing force is deviated by a predetermined angle from a direction from the side to the center of the lens (104, 222), and the engaging section and the guiding section (214, 216) are brought into contact with each other by the inwardly biasing force.