In this paper, we study the problem of secret key generation with one-way communication, where in addition to the rate limited public channel, which can be observed by both Bob and Eve, we add a secure channel, which only connects Alice and Bob. In this model, we do not pose any constraints on the sources, i.e. Bob is not degraded to or less noisy than Eve. We propose an achievability scheme, and we also suggest a converse, which meets the achievability. Therefore, we obtain the secret key capacity for this model.