As a part of programme of work on marine radioactivity in aquatic environment a few samples of algae were collected from the west coast of India and analysed for strontium, calcium and magnesium contents. Strontium to calcium atom ratio in brown algae was found to vary from 21.6 x 10^-3 to 29.5 x 10^-3 while in green and red algae it varied from 5.1 x 10^-3 to 9.1 x 10^-3 and 4.9 x 10^-3 to 5.6 x 10^-3 respectively. Brown algae accumulated strontium in preference to calcium from sea water.