The impressive protein content and rapid growth of Spirulina in entirely alkaline mediumrnhave attracted the attention of both researchers and business men. Spirulina is one of thernbest solutions for the simple production of proteinuous food supplement. The proteinrncontent of Spirulina varies between 50 % and 70%. The present study was conducted torninvestigate the possibility of producing Spirulina in outdoor cultivation technology using arnlocal product (Trona) as a substitute for the three major ingredients (NaHCO3, Na2CO3 &rnNaCl) in the Zarroukâ€™s standard culture medium. The standard medium (SM) was preparedrnfrom analytical grade chemicals and used as a control. Accordingly, a modified culturernmedium (MM) was formulated by incorporating Trona (Na2CO3.NaHCO3.2H2O). 400 mlrnbrine sample was taken from Lake Chitu. The sample was filtered, and the SM & MMrnmedia, were inoculated in triplicate with the Spirulia contained in the brine. The growth ofrnSpirulina continued for ten days with every 48 h monitoring. The data on Spirulina biomassrninterms of yield and chlorophyll content were collected. Chemical and microbiogicalrnanalyses were done. During the growth cycle, the exponential growth phase wasrnmathematically analyzed. In the scaling-up trial, a plastic dish with a diameter of 60 cm wasrnused in the place of a pond for 7 days. Accordingly, biomass determination, phyico- chmicalrnanalysis and sensory evaluation were conducted. The doubling time in the analysis of thernexponential growth phase gave close values for both media (SM = 53 h, MM = 51 h). Thernrest of the data were analyzed and means compared by t-Test using SPSS software at 5%rnsignificance level. At the end of the experiment (10th day) the mean value of biomass yieldrnwas 823.743 mg/l and 832.498 mg/l for the MM and SM respectively. Cell productivity wasrn83.221 mg l-1day-1 for the SM and 82.374 mg mgl-1day-1 for the MM. The crude proteinrncontent of biomass was 50.53% and to 51.93 % in the MM and SM respectively. The odourrnof Spirulina in SM was rated 6.333 and that of the MM was rated 5.666, while the taste ofrnthe SM was 5.888 and the MM was 5.666. Comparison of the two mean values of yield,rnproximate analysis and sensory analysis showed that there was no statistically significantrndifference between the products in the SM and MM. This justifies that Trona can be used inrnthe culture medium to cultivate Spirulina for human consumption. Finally, Spirulinarnproduction and processing technology has been outlined.rnKey words: Culture medium, production, Spirulina, Trona.