| Unit Name: | 1820 Naval Air Squadron |
| Dates: | 1944 |
| Type: | Dive-bomber squadron |
| Role: | Dive Bomber |
| Size: | Squadron |
| Command Structure: | Fleet Air Arm |
| Notable Commanders: | Lieutenant Commander(A) H.I.A. Swayne, DSC, RN |
1820 Naval Air Squadron (1820 NAS) was a Naval Air Squadron of the Royal Navy's Fleet Air Arm.
It formed at Brunswick (Maine) 1 April 1944 and embarked on in July. However its aircraft were judged unsatisfactory for their intended role and the squadron disbanded on 16 December 1944 at RNAS Burscough.
The squadron only flew one type of aircraft, the Curtiss Helldiver I.