In situ identification system for petroleum products (ES2905643) On-site identification system of petroleum products in deposits, comprising a sensor unit with a first resonant photonic transducer provided with photonic cells (11) of resonant pillars and/or photonic cells (12) of nano structured pores in resonant layers and a second transreflection photonic transducer with a transrefleration mirror (12a) preferably in NIR and/or a resonant circuit in the range of radiofrequency; Interrogation means (20) to generate an optical question signal; a unit (30) of analysis and identification for analyzing the optical interference patterns generated and the transreflection spectra or the variation of the resonance frequency and to identify the petroleum product based on said analysis; and one (40) multichannel communication line.