Abstract: Optical microscopy, scanning electron microscopy and electron probe were used to study the ingots and wire rods of the same batch of SWRH82B, in order to reveal the influence of the as-cast microstructure of the continuous casting billet on the microstructure of the hot-rolled wire rods in the subsequent process. Within 4 mm from the surface of the continuous casting billet, there is a fine-grained surface layer, from 4 mm to 57 mm is the columnar crystal zone, and the rest is the central equiaxed crystal zone, with an area ratio of about 9%. The porosity is located in the central equiaxed crystal zone and the junction zone between the columnar crystal and the equiaxed crystal, with an area ratio of 15% and a grade of 1. Through electron probe, it was found that there were different degrees of positive segregation of C, P, S, Cr and Mn in both the central equiaxed crystal zone and the columnar crystal zone. Band-like structures can be observed in the longitudinal section of the wire rod, mainly concentrated in the center, and the width and quantity gradually decrease from the center to the surface, and disappear at positions 3.5 mm and 4 mm from both sides respectively. The band-like structure is still spheroidite, but the lamellar spacing is finer than that of the matrix. The range where the band-like structure appears on the wire rod corresponds to the entire equiaxed crystal zone of the continuous casting billet and part of the adjacent columnar crystal zone. It was found that there was C negative segregation and different degrees of positive segregation of P, S, Cr and Mn in the band-like structure area. Except for C, the segregation pattern of the elements in the band-like structure is similar to that at the corresponding position in the continuous casting billet. The degree of segregation of each element in the wire rod is reduced to varying degrees compared with that in the continuous casting billet.