The aim of the research is the development of fish breeding management principles based on the analysis of mechanisms of neuroendocrine regulation of spawning. The participation of the hypothalamohypophysial neurosecretory system in fish breeding implementation was shown by histomorphological, immunohistochemical and electronicmicroscopical researches with the use of quantitative morphometry. The activation of nonapeptide neurohormones discharge into blood circulation from posterior neurohypophysis at the beginning of spawning and the following decrease of functional activity of system after it are revealed in every one-time spawning fish species idependently of its season (genera of spring-, autumn- and winterspawning: Acipenser, Oncorhynchus, Lota). The similar reaction of neurosecretory system is observed morphologically under the experimental stress –impacts of hypertonic medium on adult acipenseridae fish. The diphasic reaction of neurosecretory system conforming to stages of an alarm and a resistance of stress, is considered to be the reflection of its participation in protective-adaptive reactions of an organism to a physiological stress arising at breeding period of one-time spawning polycyclic fishes. At monocyclic species at once after spawning there becomes the blockage of function of releasing of neurohormones from posterior neurohypophysis corresponding to supernatural inhibition of system at disstress. Discussion of the functional role of nonapeptide neurohormones in implementation of reproduction is based on the analysis of morphofunctional mechanisms of neurosecretory system participation in spawning. The constructive schemes of neurosecretory system participation in all phases of spawning are provided. As a result basic principles of the effective management of fish reproduction are developed.