According to one embodiment, a data transmission device, includes: a wireless transmitting circuitry transmitting a wireless signal; measurement circuitry measuring a state of a measurement target at a first sampling rate and acquiring a first measurement value of the state of the measurement target; and controlling circuitry determining whether the first measurement value satisfies a first condition based on a first threshold value. The wireless transmitting circuitry transmits the plurality of first measurement values acquired before the first condition is satisfied when the first condition is satisfied. The measurement circuitry switches the first sampling rate to a second sampling rate higher than the first sampling rate when the first condition is satisfied, measures a state of the measurement target at the second sampling rate, and acquires a second measurement value of the state of the measurement target. The wireless transmitting circuitry transmits the second measurement value.