A lens system comprising, in order from an object side: a first lens group G1; and a second lens group G2 having positive refractive power; the first lens group G1 including a sub-lens group GS11 having positive refractive power, and a sub-lens group GS12 having negative refractive power, the sub-lens group GS12 having negative refractive power including a meniscus lens having a convex surface facing the object side, given conditions being satisfied, thereby providing a lens system having high optical performance with excellently correcting various aberrations, and an optical apparatus equipped therewith.