The invention discloses a preparation method of a multi-doped silicon ingot, the multi-doped silicon ingot and a silicon chip. The preparation method comprises the following steps: mixing a silicon material, a boron-silicon alloy, a phosphorus-silicon alloy and a gallium alloy so as to obtain a mixed material, wherein the concentration ratio of silicon to boron to phosphorus to gallium is 1:(5.1*10<-8>-1.1*10<-6>):(6.4*10<-10>-3.1*10<-6>):(2.0*10<-9>-4.2*10<-5>); and performing melting, recrystallization and annealing cooling on the obtained mixed material so as to obtain the multi-doped silicon ingot. The multi-doped silicon ingot is prepared by using the preparation method. The silicon chip is prepared from the multi-doped silicon ingot. The multi-doped silicon ingot prepared by using the preparation method disclosed by the invention is low in boron concentration and has the advantages of being good in resistance distribution uniformity, long in minority carrier lifetime, and the like, a solar battery prepared from the multi-doped silicon ingot is high in photoelectric conversion efficiency and low in light degradation, and great significances can be achieved for wide applicationof solar batteries.