To provide a biological toilet by which a favorable decomposing treatment with bacteria becomes possible without applying an excessive load to each section at the time of rotation while aiming at the performing of a stir-mixing of excrement and a chip for decomposition under a stable state.

The biological toilet 1 includes: a chair section; a toilet body section 2 having a toilet tank 8 in which a stirring space 7 for stir-mixing excretion which has passed the passing hole 9a of a toilet seat 9 opened upward and has been housed is formed; the chip for decomposition which is housed in the stirring space 7 of the toilet tank 8 in advance, and consists of bacteria and the wood chip for treating the housed excretion by utilizing the decomposing work of the bacteria; a stirring mechanism section 3 for stir-mixing the excretion and the chip for decomposition in the stirring space 7 at a specified rotation number; and a stirring driving section 5 which generates a rotation-driving force for performing the stir-mixing by the stirring mechanism section 3.