Disclosed are methods and kits for measuring in situ the activity and amount of an enzyme in a sample using a single measurement system. The method includes the steps of: (a) contacting a sample to a capturing agent having the capacity to bind to the enzyme to be analyzed and immobilized on a solid matrix; (b) measuring the activity of the enzyme captured by the capturing agent; (c) contacting a detection antibody specific to the enzyme captured by the capturing agent; and (d) detecting an antigen-antibody complex formed in the step (c). There is no need for separate measurement system to measure the activity and amount of an enzyme, as well as the above methods and kits permit to measure the precise activity and amount of an enzyme simultaneously because the measurement of enzyme activity and amount is carried out in a single and same measurement system as to the same sample in almost simultaneous manner.