An entity identity validity verification method with a plurality of TTPs being involved, wherein the method involves an entity A, an entity B, a trusted third party TTP A and a trusted third party TTP B, the TTP A is capable of verifying validity of an identity of the entity A, the TTP B is capable of verifying validity of an identity of the entity B, the entity A trusts the TTP A, the entity B trusts the TTP B, and wherein the method comprises: step 1) transmitting, by the entity B, a message 1 to the entity A, wherein the message 1 comprises identity information I B of the entity B; step 2) transmitting, by the entity A, a message 2 to the trusted third party TTP A after the entity A receives the message 1, wherein the message 2 comprises I B and a random number R A generated by the entity A; step 3) transmitting, by the trusted third party TTP A, a message 3 to the trusted third party TTP B after the trusted third party TTP A receives the message 2 transmitted by the entity A, wherein the message 3 comprises I B and a random number R TPA generated by the TTP A; step 4) after the TTP B receives the message 3 transmitted by the TTP A, verifying, by the TTP B, the validity of the identity of the entity B based on I B to acquire a verification result Res B, and transmitting, by the TTP B, a message 4 to the TTP A, wherein the message 4 comprises a token TokenTPBA, wherein TokenTPBA comprises Res B and a first signature of the TTP B, wherein signature objects of the first signature of the TTP B comprise R TPA and Res B; step 5) after the TTP A receives the message 4 transmitted by the TTP B, verifying, by the TTP A, the first signature of the TTP B in TokenTPBA; after the first signature of the TTP B passes the verification performed by the TTP A, checking, by the TTP A, whether R TPA acquired from the message 4 is the same as the random number R TPA in the message 3 transmitted by the TTP A to the TTP B; if R TPA acquired from the message 4 is the same as the random number R TPA in the message 3 transmitted by the TTP A to the TTP B, constructing a message 5 and transmitting the message 5 to the entity A by the TTP A, wherein the message 5 comprises a token TokenTA, wherein TokenTA comprises Res B and a first signature of the TTP A, wherein signature objects of the first signature of the TTP A comprise Res B and R A; and step 6) after the entity A receives the message 5 from the TTP A, verifying, by the entity A, the first signature of the TTP A in TokenTA; after the first signature of the TTP A passes the verification performed by the entity A, checking, by the entity A, whether R A acquired from the message 5 is the same as the random number R A in the message 2 transmitted by the entity A to the TTP A; if R A acquired from the message 5 is the same as the random number R A in the message 2 transmitted by the entity A to the TTP A, determining, by the entity A, the validity of the identity of the entity B based on the verification result Res B. step 1) transmitting, by the entity B, a message 1 to the entity A, wherein the message 1 comprises identity information I B of the entity B; step 2) transmitting, by the entity A, a message 2 to the trusted third party TTP A after the entity A receives the message 1, wherein the message 2 comprises I B and a random number R A generated by the entity A; step 3) transmitting, by the trusted third party TTP A, a message 3 to the trusted third party TTP B after the trusted third party TTP A receives the message 2 transmitted by the entity A, wherein the message 3 comprises I B and a random number R TPA generated by the TTP A; step 4) after the TTP B receives the message 3 transmitted by the TTP A, verifying, by the TTP B, the validity of the identity of the entity B based on I B to acquire a verification result Res B, and transmitting, by the TTP B, a message 4 to the TTP A, wherein the message 4 comprises a token TokenTPBA, wherein TokenTPBA comprises Res B and a first signature of the TTP B, wherein signature objects of the first signature of the TTP B comprise R TPA and Res B; step 5) after the TTP A receives the message 4 transmitted by the TTP B, verifying, by the TTP A, the first signature of the TTP B in TokenTPBA; after the first signature of the TTP B passes the verification performed by the TTP A, checking, by the TTP A, whether R TPA acquired from the message 4 is the same as the random number R TPA in the message 3 transmitted by the TTP A to the TTP B; if R TPA acquired from the message 4 is the same as the random number R TPA in the message 3 transmitted by the TTP A to the TTP B, constructing a message 5 and transmitting the message 5 to the entity A by the TTP A, wherein the message 5 comprises a token TokenTA, wherein TokenTA comprises Res B and a first signature of the TTP A, wherein signature objects of the first signature of the TTP A comprise Res B and R A; and step 6) after the entity A receives the message 5 from the TTP A, verifying, by the entity A, the first signature of the TTP A in TokenTA; after the first signature of the TTP A passes the verification performed by the entity A, checking, by the entity A, whether R A acquired from the message 5 is the same as the random number R A in the message 2 transmitted by the entity A to the TTP A; if R A acquired from the message 5 is the same as the random number R A in the message 2 transmitted by the entity A to the TTP A, determining, by the entity A, the validity of the identity of the entity B based on the verification result Res B.