A method for preparing a penetrating-type silver-copper composite ingot, comprising: using a group of irregularly shaped rolls, the irregularly shaped rolls being a pair of working rolls (2, 3) in a roll system of a four-roll solid-phase composite rolling mill, and grooves (5) being provided at the central positions of the working rolls; manufacturing a copper frame having a fixed width and corresponding copper bars and silver bars according to a negative tolerance of the width of the grooves of the irregularly shaped rolls, and carrying out surface treatment on the copper frame, the copper bars, and the silver bars; alternately and tightly placing different quantities of copper bars and silver bars into the copper frame according to requirements to form a composite blank, i.e., a composite ingot. The present invention also relates to a method for preparing a penetrating-type silver-copper composite strip. The silver-copper composite strip is manufactured by processing the silver-copper composite ingot prepared by the method for preparing a penetrating-type silver-copper composite ingot. The composite ingot manufactured using a penetrating-type method features a simple structure and is easy to splice, such that the subsequent processing technology is optimized and the production period is shortened. By means of the improvement on the roll system of the solid-phase composite rolling mill, the bonding strength of silver and copper side composite strips is effectively improved.