It is the object of the present invention to provide a processing apparatus, a tree-type network system, processing program and recording method that are capable of performing requests to a higher-order apparatus at the same time, while reducing the load that is concentrated in the communication path upstream in the network. One node apparatus which is provided with tree-type network system including broadcasting apparatus sending inquiry information as request-reception-begin data etc. for requesting sending response message as select-node information etc. to a plurality of node apparatus, receiving inquiry information that is sent from other processing apparatus that is connected in a higher-order layer above the processing apparatus, transferring to other processing apparatuses that are connected in a lower-order layer below the processing apparatus, receiving the reply-result information that is sent from other processing apparatus, creating its reply-result information based on own processing apparatus, and replying created reply-result information based on reply information included in reply-result-information and created reply information to other processing apparatus that is connected in a higher-order layer.