The results of local investigations of Ar+-laser plasma parameters by a new pulsed single-probe method are presented. The experiments were carried out in a 10-mm-bore tube at discharge currents of 60-80 A and argon pressure of 0.2-1 torr. Electron concentrations and temperature distributions over the discharge-tube radius have been determined. Based on the results obtained, a number of Ar+-laser plasma parameters have been estimated. Our results are compared with the available model theories of the Ar+ laser.