Diana Zagainova (born 20 June 1997 in Vilnius, Lithuania) is a Lithuanian triple jumper.
On 30 June 2019 in La Chaux-de-Fonds, Diana Zagainova broke the Lithuanian record with a mark of 14.43 m (+ 1,8 m/s).
She improves her personal best by 30 centimetres and adds 17 centimetres to the previous national record set by Dovile Dzindzaletaite 12 days prior.