This paper presents a numerical investigation of cracking behaviour of rock-like disc containing one circular inclusion subjected to diametral compression, which is validated by physical tests in terms of the crack patterns and stress–strain responses. The numerical results indicate that if the inclusion strength is higher or close to the matrix strength, one dominated crack can form to split the disc into two parts. Otherwise, the crack branches can be observed besides the dominated crack. The inclusion eccentricity has important influences on the crack pattern of the rock disc. If the inclusion strength is lower than the matrix strength, the horizontal eccentricity can induce to a horizontal crack. The length of the horizontal crack is close related to the eccentricity that a higher eccentricity can lead to a longer horizontal crack. The vertical eccentricity can result in crack branch, which becomes shorter as the eccentricity increases. If the inclusion strength is higher than the matrix, the horizontal and vertical eccentricity cannot lead to crack branches and only one dominated crack can be observed. The disc nominal strength increases by increasing the horizontal or vertical eccentricity both for cases of the inclusion strength lower and greater than the matrix.