Monitoring of physico-chemical parameters and microbiological quality of seawater from the main beaches of Skikda (eastern Algeria) were undertaken from June 2008 to May 2011. The results were processed by multivariate statistical approach. A work plan was adopted to evaluate the water quality of the beaches of the Gulf of Skikda. In the beginning we took samples at 14 stations (beaches), which are grouped into three sub-areas of study: SZE1: Common Skikda with 5 Stations, SZE2: Stora city with 3 stations and SZE3: City of Larbi Ben M'hidi with 6 stations. In our study, we were able to deduce that in both analyzed in the SZE1 (range of green castle) and the beaches in the SZE3 Beach 4 post their waters are acceptable compared to the rest of the beaches that are in good microbiological quality. In general we found in our study that the coastal waters of Skikda are acceptable and comply with Algerian standards . Therefore, strict control of waters of these beaches should be performed during the whole annual cycle and by specialized people, which will allow proper monitoring of these ecosystems. Analysis of variance showed a difference between the 3 years of follow-largest gap is noted for the year June 2008 to Mai 2009. Compared to Algerian standards and those of the OMS/UNEP (1983) relating to recreational water main beaches of Skikda are considered acceptable for swimming with temporary changes in microbiological quality.