PURPOSE: To carry out the contact reaction between a fluid and a gas with singificantly high efficiency by a method wherein one continuous wall surface formed from a hollow prism body of which a plan view is almost regular triangle and a side wall plate having a same shape are formed and arranged regularly and joined to form a shape, of which a plan view is honeycomb-like.

CONSTITUTION: In a fluid-fluid contact apparatus, one wall surface continued in an upward and downward direction which is formed by assembling a hollow prism body 5 of which a central portion with almost regular triangle plan view is squeezed, and side wall plates 59 having the same shape are formed. The above described side wall plates 59 can be fabricated not wastefully by taking the measure of a flat plate in a half-pitch shifted manner. The side wall plates 59 are reqularly arranged to contruct an almost honeycomb plan view and each thereof is fixed by joining to contruct a fluid-fluid contact apparatus 90A. This honeycomb body can be easily assembled in a multistage fashion in a packed tower and a wasteful space for the conventional method is avoided as well as a lot of time and labor required in assemblage and arrangement can be saved.