Phytotoxins released from plant to terrestrial and aquatic environment are recognized as an important category of environment micropollutants. The overall aim of this PhD study was to establish an efficient and reliable analytical platform that can be applied to chemical fingerprinting of phytotoxins in the environment and relate their occurrence to source plants. The entire PhD study included a four-step successive work on phytotoxins prioritization, sample preparation method development and optimization, analytical method development and optimization, and application of the established analytical tools to practical study. As outcome, a sPLE (or mSPE) -RPLC-ESI-HRMS analytical platform was established and successfully implemented in the field study of Lupinus angustifolius L. (blue lupin); new environmental relevant alkaloids and flavonoids were detected and identified in soil, drainage water and stream water; their occurrence was backtracked to the source plant, and a temporal trend was indicated. In the long run, we envision the established approach to assist the discovery of new phytotoxins in terrestrial and aquatic environment, remedy the knowledge gap on their origin, environmental occurrence and fate, and furthermore facilitate their risk assessment and safety regulation.