A new method of constructing a partial diallel cross plan using two blocked (equal block) and unblocked (unequal block) balanced incomplete block designs d(1) and d(2), where each design has two sets of parameters m(1), m(2) and n(1), n(2) and s(0) = 6 with parameters v, n, t, k and ? is proposed. Using the linear model, we estimated only the general combining ability effects. The crosses were taken based on the design parameters and each cross occurred only once in the construction of the partial diallel cross plan. When the number of lines (v) increases, the efficiency factor (Ep) and efficiency factor per cross (E*) increase. The constructed method is also illustrated with a suitable example.