Recent developments in ocean-bottom pressure gauge (OBP) networks have enabled us to continuously monitor various waves in the ocean. On 1 July, 2020, an OBP network, S-net, recorded tsunami-like pressure changes, although no earthquake was reported. These waves were well explained by a numerical simulation supposing a northward-moving atmospheric low pressure system with a maximum pressure depression of −0.5 ± 0.1 hPa and an apparent speed of 100–110 m/s. This simulation suggested that these waves were meteotsunamis. The simulation also suggested that the maximum amplitudes of the sea-surface height of ~ 2 cm were up to ~30% larger than those expected from the observed pressure if we do not consider the effect of the atmospheric pressure change. Our study showed that the S-net can detect the generation and propagation of meteotsunamis, which could not be achieved in the past when OBP networks with only a few stations were available.