Lieutenant-colonel Sir Jacob Henry Astley, 5th Baronet (12 September 1756 – 28 April 1817) was an English landowner and Member of Parliament.

[1] He was on military service in Scotland in 1797 when his mother announced his candidature for one of the seats in his father's old constituency, which had fallen vacant when Sir John Wodehouse was made a peer.

[2] Astley professed neutrality and publicly distanced himself from Coke, but he did vote with the Whigs against William Pitt the Younger's assessed taxes and land tax redemption in late 1797 and early 1798, against the refusal to enter into peace negotiations with France in 1800 and for the censure motion by Grey on 25 March 1801.

By his father's death in 1802 both his elder brothers had died and so he inherited the baronetcy and Melton Constable Hall in Norfolk.

He initiated a libel case, though the defence cited his own father's words just before his death and Astley was only awarded a fifth of the £10,000 damages he claimed.