In this study, the efficiency of β amino butyric acid (BABA) on induction of resistance against root-knot nematode (Meloidogyne incognita, PM) infection of tomato plants were evaluated. The effects of treatments were estimated by counting the number of galls, egg masses / root system and juvenile per 250 g soil. In addition, tomato plants growth parameters were estimated. Results showed that the plants which sprayed with BABA at 32 and 16 Mm gave the highest reduction in gall numbers, egg masses formation and juveniles, ( 57.87- 55.85, 60-59.48 and 49.8- 47.25 % respectively). Concerning the soil drench of BABA with 32 and 16 Mm the highest reduction in gall numbers, egg masses formation and juveniles were recorded ( 61.92- 60.05, 63.99-61.85 and 55.65- 53.38 % respectively). Treatments as well enhance both fresh and dry shoot and root system compared with inoculated control. Also, results showed that application of  BABA interior to nematode inoculation were outstanding in inducing acquired resistance for M. incognita than application at the same time or next nematode infection.