PURPOSE: To obtain a photographing lens constituted of six lenses of six groups as a whole, using a rear focus system where back focus is long and having high optical performance.

CONSTITUTION: This photographing lens is provided with a front group LF having positive refractive power on an object side and a rear group LR having positive refractive power on an image surface side by putting a diaphragm SP in between. The front group LF is provided with three lenses, that is, the 1st lens which is positive, a 2nd lens which is negative and meniscus-shaped, and whose convex surface faces the object side, and a 3rd lens which is positive and whose convex surface faces the image surface side in order from the object side. The rear group LR is at least provided with three lenses, that is, a 4th lens which is positive and whose convex surface faces the object side, a 5th lens which is negative and whose both lens surfaces are concave, and a 6th lens which is positive and whose both lens surfaces are convex, and focusing is performed by moving the rear group LR on the optical axis.