This search carried out to study the effect of treatment with some fungicides (mancozeb + metalaxyl - M, chlorothalonil ،azoxystrobin and mancozeb) in control late blight (Phytophthora infestans Mont.) on potato va. Spunta and yield in homs during two seasons 2008 and 2009. The results showed that the use of a mixture of fungicides (mancozeb + metalaxyl - M) gave the superior efficacy in controlling the disease during two seasons compared with other treatments. The percentage of effect (74.32% and 57.24%) during 2008 and 2009, respectively. While, the fungicides (mancozeb) gave the lowest effect in controlling the disease during two seasons, where as the percentage of effect (31.95% and 40%), respectively. Recorded results showed that spray of potato plant with tested fungicides increase the yield compared with untreated plants. The mixture fungicides (mancozeb + metalaxyl-M) increase in yield (35.55% and 32.285) during 2008 and 2009, at respectively. We can arrange the tested fungicides according to their the efficacy in controlling the disease and in increase the yield such as following: mancozeb +metalaxyl-M> chlorothalonil> azoxystrobin> mancozeb.