How to make space between LinearLayout children?

You should android:layout_margin<Side> on the children. Padding is internal.

Android now supports adding a Space view between views. It's available from 4.0 ICS onwards.

The API >= 11 solution:

You can integrate the padding into divider. In case you were using none, just create a tall empty drawable and set it as LinearLayout's divider:

    <LinearLayout
            android:showDividers="middle"
            android:divider="@drawable/empty_tall_divider"
...>...</LinearLayout>

empty_tall_divider.xml:

<?xml version="1.0" encoding="utf-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <size
            android:height="40dp"
            android:width="0dp"/>
</shape>