On a manifold with an almost contact metric structure (ϕ, ~ξ, η, g,X,D) and an endomorphism N : D → D, a notion of the N-connection is introduced. The conditions under which an N-connection is compatible with an almost contact metric structure ∇Nη = ∇Ng = ∇N~ξ = 0 are found. The relations between the Levi – Civita connection, the Schouten – van-Kampen connection and the N-connection are investigated. Using the N-connection the conditions under which an almost contact metric structure is an almost contact Kahlerian structure are investigated.
