Abstract: When considering the achievement of national economic growth and human life, rubber figures as one of the most important raw materials. The conventional use of rubber is mainly manufacturing tires employed by various vehicles and airplanes, while the automobile and aircraft industry are the pillar industries of the national economy in many countries. As a kind of high elasticity materials, rubber has some favorable properties (such as wearability, low vibration and noise, oil-resistance), which are not possessed by metals and other polymer materials. In view of the engineering application, rubber tribology is of importance.　Nowadays, the contact of two surfaces is a common phenomenon in nature and industry. A contact system includes material with the very low elastic modulus, e.g. rubber, is generally known as soft contact. Soft contacts are present in many practical engineering and biological applications, including tire, sealing ring, windscreen wiper, water lubricated bearings, contact lens, tongue-palate contact, micro/nano fluidic devices, and polishing pad in Chemical Mechanical Polishing(CMP). In soft contact, the contact pressure is great enough to cause large elastic deformation of one or both of the interacting solids, which would lead to the instability and nonlinear behavior at contact interface. As an example, there have been many attempts to explain the proportionality between the applied load and the worn surface. In the last decades, a great deal of tribological experimental and numerical works has carried out to understand the underlying mechanisms governing the frictional properties of rough soft contact in many applications, such as the rubber seals, grip of tires, synovial joints, and windscreen wipers. Each application would benefit from a specific result.　In addition, since the tribology of basic-parts for major equipment is an important growing interdisciplinary area, the developing of rubber and its products as well as tribology will certainly simulate its growing and increase demand for information in this field. Tribology of basic-parts were the severe competition in developed countries, and the hot spot at international research. Nevertheless, high-end seals and hydraulic parts are mainly dependent on foreign enterprises and imported technology. Nowadays, the improvement of the core manufacturing competitiveness almost depends on the break of basic-parts tribological research field. This paper reviewed the research on the in-situ testing technology and equipment for the soft contact at elastomer for the past 60 years. At the beginning, the paper mainly described the state-of-art of in-situ measurement of soft contact at basic-parts and its application on soft material seals. Clearly, more research should be done for the integration of these fields. Furthermore, in-situ observation technology of lubricating migration, observation of polymer seals contact were analyzed and discussed. As new materials and designs were developed, frictional properties were fully understood by the in-situ observation. Specifically, an attempt has been made to summarize the fundamentals of this in-situ observing method at seals for its future development. The basic capability of seals industry were analyzed and proposed, while some ideas could be borrowed from the related field of high performance bearing. Hopefully, this work can provide references for the seals industry.