Ceramsite foam concrete was produced by mixing fast-hardening sulphoaluminate cement with precast foam and ceramsite. The effect of foam concrete density and ceramsite particle size on the failure mode, peak stress, densification strain and energy absorption of ceramsite foam concrete subjected to static uniaxial compression is investigated. The experiment results indicate that remarkable non-interfacial failure is observed with higher density of foam concrete and larger particle size of ceramsite, from which the density range of foam concrete with matched strength of the three corresponding ceramsite is determined. With increasing density of foam concrete, the peak stress and energy absorption of ceramsite foam concrete remarkably improve, while the densification strain decreases. In addition, with increasing ceramsite particle size, the densification strain decreases first then increases, the peak stress increases first then decreases, and the energy absorption capacity gradually increases.