Nano-chitosan coating nano-iron oxide was prepared and its surface was modified with two different compounds (crotonaldehyde and succinic anhydride). The prepared nano-materials (Nano-CI, nano-CIC and nano-CIS) were characterized by FTIR, TGA, XRD, SEM, TEM and BET analyses. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were exhibit average size between 9.32-20.57 nm for nano-materials. Nano-CI, nano-CIC and nano-CIS sorbents were studied for adsorption of Pb(II), Cu(II) and Cd(II). The adsorption process of heavy metal ions was investigated by batch equilibrium technique and several controlling factors were studied. The maximum adsorption capacity values were distinguished in the following order Cu(II) > Pb (II) > Cd(II) as 4700, 2700, and 1800 mu mol g(-1), respectively. The adsorption equilibrium time was found at (10 - 30) min for studied heavy metal ions. The applicability of nano-CI, nano-CIC and nano-CIS sorbents to absorb toxic heavy metal ions from sea water and wastewater samples was tested by using micro-column technique. The effect of adsorption temperature (25, 35, 45 and 55 +/- 1 degrees C) on the adsorption of heavy metals by nano-CI, nano-CIC and nano-CIS adsorbents was also investigated. The pseudo-second order is the best and more fitted for the adsorption reactions. Langmuir is the best fitted for removal of the studied metals.