A biological simulation program which, when executed by a computer having a first processor (14b, 24b) and a second processor (14a, 24a), causes the computer to perform a biological simulation method comprising: calculating (S207, S307) a behavior of a micro model that has node points and that is a model of a material contained in a cell of an organ of a biological body, the organ being modelled by a macro model that has node points, the calculating calculates displacements (x M,e) of the node points based on a simulation result of the micro model at each time step; calculating a force that is applied to the node points of the macro model; calculating (S213, S310) a behavior of the macro model based on the calculated force that is applied to the node points of the macro model, the calculating calculates displacements (x c) of the node points based on a simulation result of the macro model at each time step; calculating (S209, S314) a behavior of a meso model that has node points and that is a model of the cell, based on the calculated behavior of the micro model used in a biological simulation of the material, the calculating calculates displacements (x F,e) of the node points based on a simulation result of the meso model at each time step; updating (S219, S317) the behavior of the meso model of the cell, based on the calculated behavior of the macro model used in a biological simulation of the organ, in accordance with displacements (x c, x F,e) of the node points of the macro model and the meso model; and updating (S220, S318) the behavior of the micro model of the material, based on the updated behavior of the meso model used in a biological simulation of the cell, in accordance with displacements (x c, x F,e) of the node points of the meso model and the macro model, wherein the biological simulation program causes: the first processor (14b, 24b) to calculate the behavior of the macro model, and the second processor (14a, 24a) to calculate the behavior of the micro model, calculate the force that is applied to node points of the macro model, calculate the behavior of the meso model, update the behavior of the meso model, and update the behavior of the micro model. calculating (S207, S307) a behavior of a micro model that has node points and that is a model of a material contained in a cell of an organ of a biological body, the organ being modelled by a macro model that has node points, the calculating calculates displacements (x M,e) of the node points based on a simulation result of the micro model at each time step; calculating a force that is applied to the node points of the macro model; calculating (S213, S310) a behavior of the macro model based on the calculated force that is applied to the node points of the macro model, the calculating calculates displacements (x c) of the node points based on a simulation result of the macro model at each time step; calculating (S209, S314) a behavior of a meso model that has node points and that is a model of the cell, based on the calculated behavior of the micro model used in a biological simulation of the material, the calculating calculates displacements (x F,e) of the node points based on a simulation result of the meso model at each time step; updating (S219, S317) the behavior of the meso model of the cell, based on the calculated behavior of the macro model used in a biological simulation of the organ, in accordance with displacements (x c, x F,e) of the node points of the macro model and the meso model; and updating (S220, S318) the behavior of the micro model of the material, based on the updated behavior of the meso model used in a biological simulation of the cell, in accordance with displacements (x c, x F,e) of the node points of the meso model and the macro model, wherein the biological simulation program causes: the first processor (14b, 24b) to calculate the behavior of the macro model, and the second processor (14a, 24a) to calculate the behavior of the micro model, calculate the force that is applied to node points of the macro model, calculate the behavior of the meso model, update the behavior of the meso model, and update the behavior of the micro model. the first processor (14b, 24b) to calculate the behavior of the macro model, and the second processor (14a, 24a) to calculate the behavior of the micro model, calculate the force that is applied to node points of the macro model, calculate the behavior of the meso model, update the behavior of the meso model, and update the behavior of the micro model.