To provide an imaging apparatus and video camera using the same that gives superior imaging performance to be maintained, by reducing the variations in the imaging position that accompanies the temperature change.

An imaging apparatus includes of five groups of a first lens group, second lens group, third lens group, fourth lens group and fifth lens group in order from an object side to an image sensor side and includes a plastic lens and a tubular holding lens barrel. The plastic lens is disposed in the third lens group and has a positive refractive power and a temperature coefficient of a refraction factor is negative. The holding lens barrel holds the third lens group in the vicinity of one terminal portion and holds an image sensor in another terminal portion. Then, the imaging apparatus is configured to make the variations in the imaging position in the third lens group with respect to the predetermined temperature change coincident with an elongation/contraction amount of the holding lens barrel, with respect to the predetermined temperature change.