Robert George Chadwick Armstrong (12 August 1836 – 9 June 1863) was an English cricketer.
He was born at Gravesend, Kent and played nine times for Kent County Cricket Club between 1859 and 1861.
Armstrong made his first-class cricket debut for Kent against Middlesex in 1859.
He made eight further first-class appearances for the county, the last of which came against England in 1861.
In his nine first-class matches, he scored 76 runs at an average of 6.90, with a high score of 10 not out.He died at Peckham in London on 9 June 1863.