Three activation counters were constructed by thin wall Geiger and were placed in different angels with respect to anode axis; 0A degrees, 45A degrees, 90A degrees; where the Geigers have 20 cm distance from anode top of the 2.5 kJ SBUPF1 plasma focus device. The counters were calibrated by a 5 Ci Am-Be neutron source with source removal method. A computer program receives the Results of each plasma focus experiment and background count rates, estimates the angular distribution of neutron emission and calculates the neutron yield of each shot. The neutron yield of the device was measured about 6 x 10(7) neutrons per shot. The results, indicate that using three counters (instead of one counter in 0A degrees) in different angles for determination of total neutron yield, gives a more accurate measurement (up to 28% is measured in sample shots), and this error is bigger in those shots that thermonuclear fusion mechanism have greater share in neutron production.