With the rapid development of satellite communication, integrated satellite and terrestrial networks have become a research hotspot. However, serious security problems may be resulted from the heterogeneity between satellite and terrestrial networks. The introduction of blockchain can effectively improve the safety of data storage and transmission. Therefore, we propose a technical architecture and a software prototype design scheme of blockchain for resource-limited satellite-terrestrial integrated network. It is designed as an eight-layer and two-vertical technical architecture. A prototype software system is developed according to the modular design requirements of blockchain. Experiments were implemented to demonstrate the feasibility and effectiveness of the proposed architecture under the condition that computing and storage resources are limited in satellite nodes. Experimental results show that the Random Access Memory (RAM) footprint would experience overflow first, and the CPU utilization rate would also be close to the upper limit. Therefore, the priority order of resources could be defined as RAM, CPU, and bandwidth resources, indicating the research direction of lightweight blockchain for resource-limited satellite-terrestrial integrated network.