Low-carbon steel is widely used for household appliance and automotive panel steel because of its excellent plasticity.Unfortunately,yield point phenomena easily appear in the low-carbon steel produced by a continuous annealing process and cause degradation to the surface quality during processing.The effect of the coiling temperature(600-750 ℃)and annealing temperature(740-820 ℃)on the yield point behavior is studied.Tensile tests show that coiling temperature has a greater effect on yield point elongation(YPE)and aging index(AI)than the annealing temperature.Microstructure observations show that coiling temperature at 750 ℃ would make the micron-sized carbides appearing at the grain boundary disappear and a number of dispersed nanoscale carbides precipitate in grain interior,corresponding to the highest solid solution car-bon content in the matrix of 750 ℃ coiled sample.The experimental results suggest that AI rather than YPE has a positive relationship with the solid solution carbon content of the low-carbon steel.And YPE has a positive relationship with the upper/lower yield strength.