To study the local resistance adjacent influence of pressure pipes and its effect on the total local head loss, the relation between total local resistance coefficient and relative distance has been researched with model test method. The results showed: when the relative distance of orifice plate is equal or more than 9 (L_s／d≥9), the maximum relative error between the calculated and measured values of the total local head loss caused by orifice plate is less than 1.2％; when the relative distance of orifice plate is less than 9 (L_s／d＜9), the measured value is much less than the calculated value, and the maximum relative error is up to 197.6％; when the relative distance is large, it is not necessary to consider the influence of space among orifice plate; when the relative distance is small, orifice plate will influence each other with the relationship that the space more small, the influence more clear. So it is necessary to consider the local resistance adjacent influence when calculate the total local head loss and correct the calculated formula with adjacent influence coefficient.