A time label combination method, comprising the steps: collecting data acquisition system digital measurement values and establishing a database for the measured values identifying atomic time label quantities and shape fluctuation statistics estimating a covariance matrix of each atomic time label according to the least squares criterion, giving the time label combination. Also provided is a time label combination system, comprising a low-dose pre-acquisition data module, a digital identification module, a quantitative variance calculation module, and a time label combination parameter calculation module. By means of using the described time label combination method and system, system and resolution is effective increased, and the invention is particularly suitable for nuclear instrument time acquisition.
