Abstract：One of the fundamental primitives in modern cryptography is the cryptographic hash functions, often informally called hash functions. They are used to compress messages of arbitrary length to fixed length hash values which are also called hash codes, message digests or digital fingerprints. A primary motivation for cryptographic hash functions is that they serve as compact representative images of input messages, which they can uniquely identify. Changing a single letter will change most of the digits in the hash code. The most common cryptographic uses of hash functions are with digital signature and for data integrity. Hash functions are frequently used in digital signature schemes to compress large messages for processing by public-key cryptosystems such as RSA. They are also used to design message authentication codes (MACs) and many secure cryptographic protocols. Hash functions occur as components in various cryptographic applications (e.g. protection of pass-phrases, protocols for payment, broadcast authentication etc.), where usually their property as a computational one-way function is used. So the study of the hash functions is of great significance in the cryptanalysis field.