The objective of this study was determination of anthocyanins, polyphenols and vitamine C content and estimation of antioxidant activity in strawberry juices with and without 0,1% high-methoxyl pectin addition. Influence of storage time on antioxidants contents in juices was also examined. The juices were stored for 3 months at 4°C in dark place. Fresh juices with and without high methoxyl pectin addition characterized respectively 1,06 mmoles/100 ml and 1,08 mmoles/100 ml of antioxidant activity. In the same juices antocyanins content were 12,2 and 14,2 mg/100ml, respectively and polyphenols content were 144,6 and 146,0 mg/100 ml respectively. Content of determinated compounds was decreasing during storage, but in juices with high-methoxyl pectin polyphenols and antioxidant activity loss were significantly smaller.