Nanocarriers has become a promising solution to anti-cancer drug delivery due to their enhanced stability and accurate targeting. However, current nanocarriers exhibit limited clinical performance since various barriers exist in blood circulation, tumor tissues and intracelluar environment. To fit in these environments during delivery, we design and synthesize an environmentally responsive protein carrier, which assembles from two kinds of polypeptide chains connected by leucine zipper coiled coils. The coils are fused with stable hydrophobic domains and functional membranes to form an amphiphilic protein carrier. In the physiological blood circulation, the surface of the carriers hides the carriers from the non-specific adsorption by macrophages; while the blocks inside the carriers are exposed in response to the tumor micro-environment so that the carriers can penetrate cell membranes and then release drugs. Our approach is demonstrated to potentially offer improved delivery efficiency and accuracy for anti-cancer drugs and might be practical in future.