To solve the expression \(\left( -\frac{1}{3} \right)^7 \cdot \left( -\frac{1}{3} \right)^9 \div \left[ \left( -\frac{1}{3} \right)^3 \right]^5\), we can use the properties of exponents.

First, simplify the multiplication of the first two terms:
\[
\left( -\frac{1}{3} \right)^7 \cdot \left( -\frac{1}{3} \right)^9 = \left( -\frac{1}{3} \right)^{7+9} = \left( -\frac{1}{3} \right)^{16}
\]

Next, simplify the exponentiation in the denominator:
\[
\left[ \left( -\frac{1}{3} \right)^3 \right]^5 = \left( -\frac{1}{3} \right)^{3 \cdot 5} = \left( -\frac{1}{3} \right)^{15}
\]

Now, divide the two results:
\[
\left( -\frac{1}{3} \right)^{16} \div \left( -\frac{1}{3} \right)^{15} = \left( -\frac{1}{3} \right)^{16-15} = \left( -\frac{1}{3} \right)^1 = -\frac{1}{3}
\]

Therefore, the result of the expression is:
\[
-\frac{1}{3}
\]