The prepared oil-filled microcapsules were eval-uated by optical microscopy, scanning electron microscopy and particle size analysis. Results showedthat spherical microcapsules with a diameter of 10 to 45 m and a rough porous shell were obtained.Carboxylated styrene/butadiene copolymer latex films containing various levels of these microcapsuleswere subjected to various levels of pre-elongation and their tensile properties were examined. The addi-tion of oil-filled microcapsules resulted in a significant improvement in the modulus, strain-to-break,and toughness of the films. The self-healing mechanism of latex films was examined through the col-orimetric measurements of the release of dye-containing following the pre-elongation of the samples.These measurements confirmed that pre-elongation of samples resulted in the release of oil within thelatex films, hence plasticizing the surrounding polymeric network and partly restoring the mechanicalproperties of the pre-elongated films