Using a mixture of several primers, the suitability of multiprimer PCR for the early and simultaneous detection of various kinds of infectious microsporidia of silkworms was evaluated. As a result, specific DNA sequences were amplified by PCR using several primers designed for this study only when genomic DNA of the target microsporidia was used as the DNA template. However, no PCR products were obtained when genomic DNA of the silkworms or other microorganisms was used as the DNA template. In addition, specific DNA sequences were amplified by multiprimer PCR even when silkworms were infected with various kinds of microsporidia. When genomic DNA extracted from silkworm eggs infected with Nosema bombycis was used as the DNA template, the specific DNA sequences were amplified by multiprimer PCR. In addition, similar results were obtained even when genomic DNA extracted from silkworms infected with N. bombycis was used as the DNA template. These findings suggest that multiprimer PCR using several primers designed for this study is suitable for pebrine inspection of silkworm eggs.