Bî-seng-bu̍t-ha̍k (eng. microbiology) sī chi̍t mn̂g choan-bûn ián-kiù bî-seng-bu̍t ê ha̍k-būn, chia-ê seng-bu̍t it-poaⁿ seng-chûn hong-sek sī tan sè-pau, he̍k-chiá sī se-pau chi̍p-thoân. Lēng-gōa, pēⁿ-to̍k mā sī bî-seng-bu̍t-ha̍k ê ián-kiù tùi-siòng. Ki-su̍t hong-bīn, bî-seng-bu̍t-ha̍k ia̍h chhù-lí e̍k-biâu, hoat-kàⁿ, clone téng būn-tê.