13th Congress may refer to:

• 13th United States Congress
• 13th Congress of the Russian Communist Party (Bolsheviks)
• 13th Congress of the Philippines
• 13th National People's Congress
• 13th National Congress of Kuomintang

• 31st US Congress
• 31st U. S. Congress
• 31st U.S. Congress
• 31st Vanier Cup
• 31st Venice International Film Festival
• 31st Volksgrenadier Division
• 3/1st Warwickshire Yeomanry
• 3/1st Welsh Horse Yeomanry
• 3/1st Westminster Dragoons
• 3/1st Westmorland and Cumberland Yeomanry
• 3/1st West Somerset Yeomanry
• 31st Yokohama Film Festival
• 3/1st Yorkshire Dragoons
• 3/1st Yorkshire Hussars
• 31st Youth In Film Awards
• 31st Youth in Film Awards
• 31TET
• 31. Unterseebootsflottille
• 31X
• 31º Stormo
• 31 år på gress
• 31 арна
• 3 + 2
• 32
• *32