The heavy metals biosorption by alginate immobilized durian seed biomaterial has been done in dry, gel bead and non-immobilized. Immobilization of durian seed powder into alginate was able to improve the performance of the biomass in adsorption process, increasing the uptake capacity, facilitate the separation of the biomass from the solution, can be regenerated without damaging the structure of the biomass and used repeated bio-sorbent. In this study specifically studied the effect of pH on the uptake capacity of metals such as Pb(II), Cu(II), Cd(II) and Zn(II) on durian seed non immobilized and alginate immobilized biosorbent. pH was obtained for each metal ions was at pH 4-5 for Pb(II), pH 5-6 for Cu(II) and Cd(II), pH 4-5 for Zn(II) in alginate immobilized(dry and gel bead), nonimmobilized and Ca-alginate matrix respectevely. The order of the uptake capacity was: alginate immobilized dry bead>non immobilized> gel bead> Ca-alginate.