Wilhelm Christian Karl, 3rd Prince of Solms Braunfels (9 January 1759, in Braunfels – 20 March 1837, in Braunfels) was by succession an immediate Prince, then a nobleman and head of the Princely House of Solms-Braunfels, a Prussian major general and Hessian deputy.

His parents were the imperial colonel and lieutenant general of the United Provinces Ferdinand Wilhelm Ernst (1721–1783) and Countess Sophie Christine Wilhelmine of Solms-Laubach.

first daughter and second child of Christian August, Count of Solms-Laubach.

Prussian Major General Frederick William (1770–1814) was one of his younger brothers.

On 6 October 1792, he married Wild- und Rheingräfin Auguste of Salm-Grumbach (1771–1810) half-sister of Friedrich, Prince of Salm-Horstmar.