CPCB carried out ambient air quality and noise level monitoring on selected pre-Deepawali day (09.11.2020) and on Deepawali day (14.11.2020) in Delhi like previous years. Ambient Air Quality was monitored at 40 locations (3 manual stations and 37 real-time stations). Ambient Noise level was monitored at 16 locations (06 manual and 10 real-time noise monitoring stations). Three continuous air quality stations (operated by CPCB, NABL accredited) have been used for comparison with last five years’ data. Noise level and air quality (both manual and Real time) on Pre-Deepawali day (09.11.2020) and Deepawali day (14.11.2020) are presented in this report for assessment of impact of Diwali celebration.