In this paper, we introduce a new cryptographicprimitive:adaptableKP-ABEwithtimeinterval(KP-TIABE),which is an extension of key-policy attribute-based encryp-tion(KP-ABE).AdaptableKP-TIABEspecifiesadecryptiontime interval for every ciphertext such that the ciphertextcan only be decrypted within this time interval. To be moreflexible,thedecryptiontimeintervalassociatedwithacipher-text can be adjusted on demand by a semi-trusted server. Wepropose a formal model for adaptable KP-TIABE, present aconcrete adaptable KP-TIABE scheme and prove its securityunder the security model