Objective      To investigate the influences of information dissemination on the population cognition and psychological expectations at the different stages in the event of the missing Malaysia Airlines MH370.       Methods      Self-developed Missing Malaysia Airlines MH370 Mass Survey (MAMS) was used to collect the public attitudes about the event of the missing Malaysia Airlines MH370 on the Internet platforms such as Microblog

Wechat

Baidu Post Bar and so on. The results collected from 810 questionnaires from 3 stages in the event were analyzed with the software SPSS18.0.       Results      There was no significant difference in the cognition of objective facts among the different stages of the event (

P

0.05). There were significant differences in the cognition of media information (lowest the middle stage

P

0.01) and rumors (higher in the middle stage than the early stage

P

0.05) in the different stages (

P

0.01). There were significant differences in the cognition of cause in the different stages of the event (

P

0.05). There were significant differences in the cognition of positive expectation in the different stages of the event (

P

0.05)

the highest in the middle stage.       Conclusion      Significant differences are found in the cognition of clues and causes in the different stages of the event. The mass attitudes tend to be cautious and conservative when the information environment is filled with a large number of uncertain information.