The cyanobacterium Spirulina platensis is an attractive source of valuable protein for both human and animal consumption. Investigations were carried out in Chad to evaluate the influence of the production sites on the physico-chemical properties of S. platensis. Samplesfrom Artomissi, Brandi and Sugar Producing Company of Chad (CST) were analyzed and compared. The pH (H2O) in the production sites was basic and ranged from 9.98 to 10.01. The temperature also varied from 36.15°C for Artomissi to 31.3°C for Brandi. The protein content in samples significantly differed (p < 0.0001) from 50.21% for CST to 58.61% for Artomissi and Brandi. Similarly, there was a highly significant difference (p < 0.0001) between the saponin contents in samples originated respectively from Artomissi (319), Brandi (286.6) and CST (136.6 mg/100g DM). Brandi was the production site with the greatest total chlorophyll content (973.51 mg/100g DM) (p < 0.0001)), while the smallest accounted for Artomissi samples (725.62 mg/100g DM). S. platensis from Brandi (35.14%) and Artomissi (46.43%) consistently contained more phycocyanin than that of CST (10%). Apart from calcium that did not show significant difference (p = 0.224) between the production sites, the studied micro and macroelements in S. platensis significantly differed (p < 0.0001) from one production site to another. No toxic heavy metals such as nickel, chromium, sulphates, and cyanides were detected in S. platensis samples. The results reveal that macro and microelements essential to animal and human nutrition are present in S. platensis and can be in use as food supplement.