Nanoassemblies are spontaneously formed in dilute aqueous solutions by mixing of two dextrans modified with lauroyl and β-cyclodextrin moieties, respectively. This association process is mainly driven by host/guest interactions between the two polymers. The nanoassemblies' size depends on the substitution degrees of the polymers, and on the total concentration and composition of the mixtures. The results are compared to those previously obtained with adamantyl grafted dextrans. The number and the strength of the individual guest-host complexes between the two grafted dextrans is the key parameter to obtain small and stable nanoassemblies.