Abstract: In Mass spectrometry separation of ions takes place on the basis of there mass to charge ratio. Mass spectroscopy is an advanced and powerful technique for qualitative and quantitative analysis. Detector plays an important role in mass spectrometer for the separated charged ions. Results are displayed as spectra of the relative abundance of detected ions as a function of the mass-to-charge ratio. The detector with desirable properties in mass spectrometer should have high amplification, Fast time response, Low noise, High collection efficiency, Low cost, Narrow distribution of responses, Same response for all masses, Large dynamic range, Long term stability, Long life and can be Mounted outside of the vacuum if possible. Type of mass detectors and there working capacity reviewed in the present article. These mass detectors are a] Electron Multiplier, Faraday cups, Photographic plates, Scintillation counter, channel electron Multipliers, Resistive anode Encoder image Detectors, High mass detection detectors); b] Conversion Dynodes- Helium leak detectors, Advanced detectors; c] Cryogenic Detectors-Multi Pixel Photon counter and d] Other Detectors- TQD Tandem Quadrupole MS Detector, Photonics BI Polar Maldi TOf Detector and Flexar SQ 300 MS Detector. It is also observed that evoluation in mass spectrometry always takes place as per the type and need of analysis.Abstract: In Mass spectrometry separation of ions takes place on the basis of there mass to charge ratio. Mass spectroscopy is an advanced and powerful technique for qualitative and quantitative analysis. Detector plays an important role in mass spectrometer for the separated charged ions. Results are displayed as spectra of the relative abundance of detecte...Show More