The invention discloses a band-gap reference circuit free from an operational amplifier. The band-gap reference circuit comprises a band gap core unit, a clamp unit and a starting unit; the band gap core unit is used for generating zero temperature coefficient reference voltage VREF; the input end of the clamp unit is connected with clamp voltage VA and clamp voltage VB, and an output end is connected with the reference voltage VREF and formed to be a negative feedback along with the band gap core unit; the clamp unit is used for guaranteeing that the clamp voltage VA and clamp voltage VB output by the band gap core unit are equal to each other; an input end of the starting unit is connected with the clamp voltage VB, and an output end outputs a starting signal Vstart to the clamp unit forguaranteeing that the clamp unit and the band gap core unit can rapidly enter a normal working state in the process of electrifying. For not adopting the operational amplifier structure, the influence of offset voltage on the reference voltage VREF is weakened, and the temperature coefficient of the reference voltage is reduced by a resistance proportional compensation technology. The band-gap reference circuit is featured by low temperature offset, low power consumption, and simple structure; the band-gap reference circuit can be applied to a chip with high requirement on static power consumption.