The actress, who plays Eva Price in the ITV1 soap, was celebrating her 29th birthday when candles from her Disney themed birthday cake ignited her hair.
Co-star Antony Cotton – who plays Sean Tully – rushed to put out the flames before they spread any further.
Taking to Twitter, Cotton later posted a photo of Tyldesley with the cake, saying: “Birthday update: @Cath_Tyldesley has just set her hair on fire. Actual fire. I put it out but the #privateroom smells of burning bush…”
Tyldesley added of the incident: “Can’t believe my hair caught fire on my birthday cake! God damn you hairspray!
“Tonight @antonycotton saved my life… Now my hair smells.. Bad…”